| Time-delayed second-harmonic generation in an atomic vapor of cesium University of California, Berkeley | Publication | 1998-10-01 | A. Lvovsky, S. R. Hartmann |
| Time-delayed second-harmonic generation in atomic Cs vapor University of Calgary | Publication | 1997-09-01 | A. Lvovsky, S. R. Hartmann |
| Cabello’s Nonlocality and Linear Optics Universitat Konstanz | Publication | 2002-02-01 | A. Lvovsky |
| Quantum State Reconstruction of the Single-Photon Fock State Universitat Konstanz | Publication | 2001-07-01 | A. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, S. Schiller |
| Superradiant self-diffraction University of California, Berkeley | Publication | 1999-05-01 | A. Lvovsky, S. R. Hartmann |
| Continuous-variable optical quantum-state tomography University of Calgary | Publication | 2009-03-01 | A. Lvovsky, M. G. Raymer |
| Observation of micro–macro entanglement of light University of Calgary | Publication | 2013-07-01 | A. Lvovsky, R. Ghobadi, A. Chandra, A. Prasad, C. Simon |
| Photonic qubits: A quantum delivery note University of Calgary | Publication | 2012-12-01 | A. Lvovsky |
| Photonic qubits: A quantum delivery note (News and Views article) University of Calgary | Publication | 2013-01-01 | A. Lvovsky |
| Decomposing a pulsed optical parametric amplifier into independent squeezers University of Calgary | Publication | 2007-01-01 | A. Lvovsky, W. Wasilewski, K. Banaszek |
| Quantum Communication, Measurement and Computing (QCMC): the Ninth International Conference University of Calgary | Publication | 2009-01-01 | A. Lvovsky |
| Continuous-variable experiments with optical qubits University of Calgary | Publication | 2005-01-01 | A. Lvovsky, S. Babichev, J. Appel |
| Conditionally prepared photon and quantum imaging Universitat Konstanz | Publication | 2004-01-01 | A. Lvovsky, T. Aichele |
| Photons and quantum technologyAlthough the concept of the light particle has been introduced more than a hundred years ago, it is only now that the technology has reached the level enabling us to generate single photons and experiment with them. Such experiments reveal numerous paradoxes associated with the deeply nonclassical nature of the photon and thus help us understand the very essence of quantum mechanics. Its nonclassical properties make the photon an irreplaceable tool of communication in quantum information technology. University of Calgary | Presentation | 2005-03-31 | A. Lvovsky |
| How to measure optical qubits? University of Calgary | Presentation | 2005-05-13 | A. Lvovsky |
| Raman adiabatic transfer of optical states in multilevel atoms University of Calgary | Presentation | 2006-12-15 | A. Lvovsky |
| Electromagnetically-induced transparency in multilevel atoms University of Calgary | Presentation | 2006-12-12 | A. Lvovsky |
| Photons and quantum information> Although the concept of the light particle has been introduced more than a hundred years ago, it is only now that the technology has reached the level enabling us to generate single photons and experiment with them. I will present a series of experiments which explore various aspects of the electromagnetic field quanta and reveal their potential for quantum information processing.
University of Calgary | Presentation | 2006-07-24 | A. Lvovsky |
| Quantum ComputingIt seems merely a matter of time until human technology crosses the quantum boundary, and there is little doubt this is to happen within one generation. Quantum mechanical phenomena and the laws of quantum mechanics will be used to meet new technological challenges. Quantum mechanics will leave the labs of physicists, biologists and chemists and will find new applications in industry, services and potentially even in private households. The gap between the quantum and the classical world will be closed. University of Calgary | Presentation | 2006-02-09 | A. Lvovsky |
| Photons and quantum IT University of Calgary | Presentation | 2006-11-16 | A. Lvovsky |
| Quantum optical technology at the single-photon level and beyondLatest progress in quantum optical engineering allows us to synthesize increasingly complex quantum states of light. At the same time, the progress in optical homodyne tomography, particularly in application to "discrete-variable" optical states that are useful in quantum information technology, leads to fundamental improvement in the accuracy of quantum-state characterization. These developments constitute a qualitative advance in quantum optical technology because they open up a vast new region of the Hilbert space that was previously not accessible for experimental investigation. The gap between "discrete-" and "continuous-variable" quantum optics is closing. University of Calgary | Presentation | 2006-12-05 | A. Lvovsky |
| Storage of light and quantum communicationQuantum memory for light is one of the first significant
inventions of this millennium. This technology is not only important for
quantum computers, but also enables long-distance, secure quantum
communication. We shall discuss the current progress in storing light as well as the problems that need to be resolved before practical application of quantum memory becomes possible.
University of Calgary | Presentation | 2008-11-26 | A. Lvovsky |
| How memory for light helps quantum communicationOptical communication protocols that employ quantum nature
of light are very secure. Their practical development is however
hindered by losses, which reduce the communication range to a few tens of kilometers. This problem can be remedied by means of quantum repeaters, which effectively enhance the data transfer rate without compromising security. Implementation of quantum repeaters requires quantum memory for light - a tool that permits high-fidelity storage and retrieval of quantum optical states. University of Calgary | Presentation | 2008-11-14 | A. Lvovsky |
| Memory for light: why, how, when?Quantum memory for light is one of the first significant inventions of this millennium. This technology is not only important for quantum computers, but also enables long-distance, secure quantum communication. During the colloquium, we shall discuss the current progress in storing light as well as the problems that need to be resolved before practical application becomes possible. University of Calgary | Presentation | 2008-11-14 | A. Lvovsky |
| Quantum refrigerator for light University of Calgary | Presentation | 2008-11-12 | A. Lvovsky |
| Towards a universal light storage machineQuantum memory for light is one of the first significant inventions of this millennium. This technology has now been tested with important quantum information primitives: single photons, squeezed and entangled states. A big question remains though: what will remain of an *arbitrary* optical state after it has been stored and retrieved? Can it still be used for the purpose it was created with? In my talk, I will address our group\'s effort to answer this question and to implement quantum memory for exotic states of light. University of Calgary | Presentation | 2008-09-11 | A. Lvovsky |
| Memory for light and quantum communication Optical communication protocols that employ quantum nature
of light are very secure. Their practical development is however
hindered by losses, which reduce the communication range by a few tens of kilometers. This problem can be remedied by means of quantum repeaters, which effectively enhance the data transfer rate without compromising security. Implementation of quantum repeaters requires quantum memory for light - a tool that permits high-fidelity storage and retrieval of quantum optical states. We will discuss ways in which such memory can be implemented, as well as the current state of the art, progress, and challenges faced by the field.
University of Calgary | Presentation | 2008-05-05 | A. Lvovsky |
| Memory for light as a component of quantum communication systemsOptical communication protocols that employ quantum nature of light are very secure. Their practical development is however hindered by optical losses, which limit the communication range to a few dozens of kilometers. This problem can be remedied by means of quantum repeaters, which reduce the effect of losses without compromising security. Implementation of quantum repeaters requires quantum memory for light - a tool that permits high-fidelity storage of quantum optical states in atomic ensembles. We will discuss ways in which such memory can be implemented, as well as the current state of the art, progress, and challenges faced by the research in the field. University of Calgary | Presentation | 2009-04-06 | A. Lvovsky |
| Constructing light: photon by photonAlthough the photon has been discovered over a century ago, it is only since the last twenty years that we have been able to controllably generate and detect certain quantum states of light. Our capabilities to produce nonclassical optical states are however still quite limited. In order to make light suitable for quantum technology applications, we have to extend the region of the Hilbert space we have access to � learn to synthesize, manipulate and characterize any arbitrary quantum state of the electromagnetic field. University of Calgary | Presentation | 2009-05-27 | A. Lvovsky |
| Making light, photon by photon University of Calgary | Presentation | 2009-07-22 | A. Lvovsky |
| Making light out of photons University of Calgary | Presentation | 2009-08-28 | A. Lvovsky |
| Making, storing and measuring light: photon by photon University of Calgary | Presentation | 2010-03-01 | A. Lvovsky |
| Peeking into quantum black boxesAssembling a quantum information processing circuit requires precise knowledge of the properties of its each component, i.e. the ability to predict the effect of the component on an arbitrary input quantum state. This knowledge is acquired through quantum process tomography - a procedure in which certain \"probe\" states are sent into the quantum \"black box\", and the corresponding outputs are measured. Surprisingly, black boxes that process quantum optical information can be completely characterized using coherent states, i.e. simple laser pulses, as the probe states. We shall discuss the theory and implementation of this procedure as well as a few examples of its practical application. University of Calgary | Presentation | 2009-11-03 | A. Lvovsky |
| The 'black box' problem for quantum light University of Calgary | Presentation | 2010-05-06 | A. Lvovsky |
| Exploring dimensions of quantum light University of Calgary | Presentation | 2010-05-04 | A. Lvovsky |
| Assembling and disassembling light (synthesis, manipulation, measurement and storage of quantum information carried by light) University of Calgary | Presentation | 2011-10-01 | A. Lvovsky |
| Quantum technology in application to light University of Calgary | Presentation | 2011-09-12 | A. Lvovsky |
| Quantum technology in application to light University of Calgary | Presentation | 2011-09-14 | A. Lvovsky |
| Quantum technology in application to light University of Calgary | Presentation | 2011-09-16 | A. Lvovsky |
| Ten years in the life of quantum light University of Calgary | Presentation | 2011-10-07 | A. Lvovsky |
| Ten years in the life of quantum light University of Calgary | Presentation | 2011-10-28 | A. Lvovsky |
| Quantum engineering of light and atoms University of Calgary | Presentation | 2011-10-24 | A. Lvovsky |
| Quantum technology in application to light and its extension to atomic ensembles University of Calgary | Presentation | 2011-12-06 | A. Lvovsky |
| Quantum technology in application to light and its extension to atomic ensembles University of Calgary | Presentation | 2011-12-08 | A. Lvovsky |
| Quantum technology in application to light and its extension to atomic ensembles University of Calgary | Presentation | 2011-12-26 | A. Lvovsky |
| Quantum technologies and singularity University of Calgary | Presentation | 2012-02-20 | A. Lvovsky |
| The Russian Quantum Center: a pilot project of setting up basic science in Skolkovo University of Calgary | Presentation | 2012-03-10 | A. Lvovsky |
| Quantum technology of light: a ten-year progress report University of Calgary | Presentation | 2012-03-22 | A. Lvovsky |
| Synthesis, manipulation and storage for applications in quantum information technology University of Calgary | Presentation | 2012-02-21 | A. Lvovsky |
| Quantum optics: from riddles to technologies University of Calgary | Presentation | 2012-10-18 | A. Lvovsky |
| Synthesis, manipulation, measurement and storage of quantum information carried by light University of Calgary | Presentation | 2012-11-05 | A. Lvovsky |
| Quantum technologies University of Calgary | Presentation | 2013-04-06 | A. Lvovsky |
| Schrödinger Cat: is entanglement and macroscopicity enough?Although the quantum nature of light has been discovered over a century ago, controlling its quantum states still presents a considerable technical challenge. The past fifteen years have shown significant progress in solving it. Using entangled light sources, linear optical transformations and conditional measurements, we are able to produce and measure increasingly complex quantum optical states. I will review some of the new states of light that have been studied in the past years, methods of their preparation and measurement. I will concentrate on the single-photon Fock state, the displaced Fock state, and the dual-rail optical qubit. Then I will show how combining these approaches lead us to a surprising new result: a micro-macro entangled optical state (Schrödinger cat) with the macroscopic part containing over a hundred million photons.
University of Calgary | Presentation | 2014-02-14 | A. Lvovsky |
| Photons and qubits in a continuous-variable aspectI review optical homodyne tomography as a method for precise characterization of photons, qubits, and elementary optical information processors. While being more challenging technically, this continuous-variable method provides much more accurate information about optical ensembles than traditional photon-counting based tech-niques. The application of continuous-variable tomography to discrete optical states creates a bridge between these two formerly distinct areas of quantum optics. University of Calgary | Presentation | 2005-11-06 | A. Lvovsky |
| New results in optical homodyne tomography and their applications to quantum information technology University of Calgary | Presentation | 2005-07-11 | A. Lvovsky |
| Homodyne tomography for quantum information: a new application for an old methodI will present a series of experiments in which we create, manipulate, characterize and apply new quantum states of the electromagnetic field for applications in quantum information processing. Our approach is unique in the way it combines traditionally discrete-variable quantum states (photons and optical qubits) as the object of investigation with homodyne tomography, a continuous-variable method of quantum state measuremnet. This method, based on phase-sensitive measurements of quantum noise staistics of the electro-magnetic field, is technically more challenging, but provides much more accurate information about optical ensembles than traditional photon-counting based techniques. By applying our approach to more and more complex quantum optical states, we not only delveop new tools of quantum information technology, but also answer some important questions of fundamental nature. University of Calgary | Presentation | 2005-06-05 | A. Lvovsky |
| Homodyne tomography of optical states and its applications in quantum technology University of Calgary | Presentation | 2005-05-17 | A. Lvovsky |
| Experimental violation of the Bell inequality in a continuous-variable settingWe violate the Bell inequality by means of measuring
phase-dependent field quadratures associated with a single photon,
delocalized over two optical modes. The quadrature data are
converted to a dichotomic format using threshold discrimination.
We discuss the loopholes arising in this experiment as well as its
application for quantum-optical information technology purposes.
University of Calgary | Presentation | 2005-05-09 | A. Lvovsky |
| The continuous-variable approach in discrete-variable quantum optics University of Calgary | Presentation | 2005-05-02 | A. Lvovsky |
| Continuous-variable experiments with optical qubits University of Calgary | Presentation | 2004-11-11 | A. Lvovsky, S. Babichev, J. Appel |
| Quantum technology and information security University of Calgary | Presentation | 2006-04-20 | A. Lvovsky |
| Electromagnetically-induced transparency in systems with multiple excited levels University of Calgary | Presentation | 2006-11-30 | A. Lvovsky, J. Appel, E. Figueroa, G. Günter, F. Vewinger, K. Marzlin |
| Photon as a qubit: A continuous-variable approachI will discuss current challenges and limitations in the experimental implementation of the photon as a qubit, with a particular emphasis on the task of characterizing quantum optical states for the purposes of quantum information technology. I will present our recent experimental achievements in applying homodyne tomography to highly nonclassical states of light such as the single-photon Fock state as well as the single- and dual-rail optical qubits and demonstrate the advantages of this quantum state measurement technique with respect to the traditional photon-counting based approach. University of Calgary | Presentation | 2004-11-30 | A. Lvovsky |
| Electromagnetically-induced transparency with clasical and nonclassical light University of Calgary | Presentation | 2007-09-14 | A. Lvovsky |
| Steering light by electromagnetically-induced transparencyFrequency conversion and routing of quantum information carried by light is of great importance for future quantum communication networks. We experimentally demonstrate a communication protocol that enables frequency conversion and routing of quantum optical information in an adiabatic and thus robust way. The protocol is based on electromagnetically-induced transparency (EIT) in systems with multiple excited levels: transfer and/or distribution of optical states between different signal modes is implemented by adiabatically changing the control fields.
Proof-of-principle experiments were performed using the hyperfine levels of Rb 87 atoms at the D1 line. First, we placed a signal pulse (resonant to the F=1, F'=2 transition) into the cell under EIT conditions created by a control laser (resonant to F=2, F'=2). This laser is adiabatically switched off while another control laser (resonant to F=2, F'=1) is switched on. The information carried by the state of the original signal pulse is then transferred to the optical mode resonant with the F=1, F'=1 transition.
The evolution of the spatial characteristics of the EIT signal field is governed by the paraxial approximation, which is equivalent to the Schrödinger equation of a free particle in space. In an EIT system with multiple excited levels, in the presence of several control fields, the signal field is subjected to a unitary transformation, which, in analogy to gauge transformations, modifies the paraxial equation, making it analogous to that of a charged Schrödinger particle in an electromagnetic field, with the quasi-potentials related to the amplitudes and phases of the two pump fields. By choosing specific spatially inhomogeneous control fields, one can steer the EIT photon inside the cell.
University of Calgary | Presentation | 2007-08-26 | A. Lvovsky |
| Quantum memory for continuous-variable optical statesWe are reporting on our progress towards universal quantum memory for light: a system that would allow storage and retrieval, with high fidelity, of an arbitrary optical state. Our apparatus employs parametric down-conversion for preparing quantum states of light, electromagnetically-induced transparency for their storage in atomic rubidium vapor and homodyne tomography for measuring the retrieved states. We demonstrate storage and retrieval of squeezed vacuum as a test of our system\'s capabilities. University of Calgary | Presentation | 2008-06-11 | A. Lvovsky |
| Quantum information with atoms and photons University of Calgary | Presentation | 2008-09-24 | A. Lvovsky |
| Electromagnetically‐induced transparency with squeezed lightWe investigate propagation and storage of pulses of squeezed vacuum in rubidium vapor under the conditions of electromagnetically-induced transparency. Quantum states of retrieved pulses are characterized by optical homodyne tomography. University of Calgary | Presentation | 2008-07-16 | A. Lvovsky |
| Electromagnetically-induced transparency for quantum optical information processingWe report storage and retrieval of pulsed squeezed vacuum in rubidium vapor using electromagnetically-induced transparency. For the first time, complete tomographic characterization of the quantum state after the storage procedure has been performed, making our setup a universal test bed for a generic quantum optical memory system.
University of Calgary | Presentation | 2008-06-30 | A. Lvovsky, J. Appel, E. Figueroa, D. Korystov, M. Lobino |
| Quantum memory for squeezed lightWe study electromagnetically-induced transparency (EIT) as a tool for slowing down and storing squeezed light. The experiments are conducted in rubidium vapour, and the squeezed vacuum state is prepared by means of an optical parametric amplifier. Full homodyne tomography of the squeezed vacuum pulse before and after the interaction with the EIT cell provides insight into the phenomena that degrade the storage fidelity. University of Calgary | Presentation | 2008-07-03 | A. Lvovsky, J. Appel, E. Figueroa, D. Korystov, M. Lobino |
| Storage of squeezed light as a step towards universal quantum memoryThe ``holy grail'' of the quantum optical memory research is a system that would allow high fidelity storage and retrieval of an arbitrary optical state. We present a functioning testbed for such a system, which brings together the preparation of the quantum state, the memory cell, and full characterization of both the input and the retrieved state in a single apparatus. As demonstration of its capabilities, we report high-fidelity storage and retrieval of the squeezed vacuum state using electromagnetically-induced transparency in atomic rubidium vapor. University of Calgary | Presentation | 2008-05-30 | A. Lvovsky |
| Memory for light and quantum communication University of Calgary | Presentation | 2008-08-13 | A. Lvovsky |
| Characterization of memory for light as a quantum-optical process University of Calgary | Presentation | 2009-07-20 | A. Lvovsky |
| Making and measuring quantum states of light University of Calgary | Presentation | 2009-07-06 | A. Lvovsky |
| Limitations on linear-optical processing of single photon efficiency University of Calgary | Presentation | 2010-08-24 | A. Lvovsky, W. D. Berry |
| Characterizing quantum optical "black boxes" University of Calgary | Presentation | 2010-05-31 | A. Lvovsky |
| Three ways to characterize a quantum-optical black box University of Calgary | Presentation | 2011-06-13 | A. Lvovsky |
| Describing quantum optical "black boxes" University of Calgary | Presentation | 2011-05-26 | A. Lvovsky |
| The Russian Quantum Centre and its planned research University of Calgary | Presentation | 2011-05-25 | A. Lvovsky |
| Technology of light at a few-photon level University of Calgary | Presentation | 2010-10-02 | A. Lvovsky |
| Making a large entangled state from a small one University of Calgary | Presentation | 2013-06-21 | A. Lvovsky, A. Prasad, R. Ghobadi, A. Chandra, C. Simon, Y. Kurochkin |
| Technology of light as a harmonic oscillator University of Calgary | Presentation | 2013-07-29 | A. Lvovsky |
| Micro-macro entanglement in optics University of Calgary | Presentation | 2013-07-24 | A. Lvovsky, R. Ghobadi, Y. Kurochkin, C. Simon |
| Optical quantum memory University of Calgary, The University of Calgary | Publication | 2009-01-01 | A. Lvovsky, B. C. Sanders, W. Tittel |
| Squeezed light University of Calgary | Publication | 2014-01-01 | A. Lvovsky |
| Observation of micro-macro entanglement of light University of Calgary | Publication | 2013-07-01 | A. Lvovsky, R. Ghobadi, A. Chandra, A. Prasad |
| Optical mode characterization of single photons prepared by means of conditional measurements on a biphoton state Universitat Konstanz | Publication | 2002-02-01 | T. Aichele, A. Lvovsky, S. Schiller |
| Bulk contribution from isotropic media in surface sum-frequency generation Universitat Konstanz | Publication | 2002-11-01 | H. Held, A. Lvovsky, X. Wei, Y. R. Shen |
| Pulsed squeezed light: Simultaneous squeezing of multiple modes University of Calgary | Publication | 2006-06-01 | W. Wasilewski, A. Lvovsky, K. Banaszek, C. Radzewicz |
| Linear-Optical Processing Cannot Increase Photon Efficiency University of Calgary | Publication | 2010-11-01 | D. W. Berry, A. Lvovsky |
| Preservation of loss in linear-optical processing University of Calgary | Publication | 2011-10-01 | D. W. Berry, A. Lvovsky |
| Creating and Detecting Micro-Macro Photon-Number Entanglement by Amplifying and Deamplifying a Single-Photon Entangled State University of Calgary | Publication | 2013-04-01 | R. Ghobadi, A. Lvovsky, C. Simon |
| Efficiency limits for linear optical processing of single photons and single-rail qubits University of Calgary | Publication | 2007-01-01 | D. W. Berry, A. Lvovsky, B. C. Sanders |
| Interconvertibility of single-rail optical qubits University of Calgary | Publication | 2006-01-01 | D. W. Berry, A. Lvovsky, B. C. Sanders |
| Remote preparation of arbitrary states of an atomic collective University of Calgary | Presentation | 2011-08-12 | A. MacRae, A. Lvovsky |
| Quantum efficiency of an optical state: a general theory University of Calgary | Presentation | 2011-07-11 | W. D. Berry, A. Lvovsky |
| On quantum efficiencies of optical states University of Calgary | Presentation | 2011-06-07 | W. D. Berry, A. Lvovsky |
| Quantifying optical losses University of Calgary | Presentation | 2011-06-02 | W. D. Berry, A. Lvovsky |
| Conservation of vacuum in an interferometer University of Calgary | Presentation | 2011-05-10 | W. D. Berry, A. Lvovsky |
| Conservation of vacuum in an interferometer University of Calgary | Presentation | 2011-03-24 | W. D. Berry, A. Lvovsky |
| Experimental vacuum squeezing in rubidium vapor via self-rotation Universitat Konstanz | Publication | 2003-08-01 | J. Ries, B. Brezger, A. Lvovsky |
| Remote Preparation of a Single-Mode Photonic Qubit by Measuring Field Quadrature Noise University of Calgary, Universitat Konstanz | Publication | 2004-01-01 | S. Babichev, B. Brezger, A. Lvovsky |
| Evaluation of Surface vs Bulk Contributions in Sum-Frequency Vibrational Spectroscopy Using Reflection and Transmission Geometries † Universitat Konstanz | Publication | 2000-04-01 | X. Wei, S. Hong, A. Lvovsky, H. Held, Y. R. Shen |
| Raman adiabatic transfer of optical states in multilevel atoms University of Calgary | Publication | 2006-01-01 | J. Appel, K. -. Marzlin, A. Lvovsky |
| Time-resolved probing of the ground state coherence in rubidium University of Calgary | Publication | 2007-01-01 | M. Oberst, F. Vewinger, A. Lvovsky |
| Note: A monolithic filter cavity for experiments in quantum optics University of Calgary | Publication | 2012-01-01 | P. Palittapongarnpim, A. MacRae, A. Lvovsky |
| Distillation of The Two-Mode Squeezed State University of Calgary | Publication | 2014-02-01 | Y. Kurochkin, A. S. Prasad, A. Lvovsky |
| Efficiencies of quantum optical detectors University of Calgary | Publication | 2014-01-01 | D. Hogg, D. W. Berry, A. Lvovsky |
| A monolithic filter cavity for experiments in quantum optics University of Calgary | Publication | 2012-01-01 | P. Palittapongarnpim, A. MacRae, A. Lvovsky |
| Multimode electromagnetically-induced transparency on a single atomic line University of Calgary | Publication | 2009-01-01 | G. Campbell, A. Ordog, A. Lvovsky |
| Versatile digital GHz phase lock for external cavity diode lasers University of Calgary | Publication | 2009-01-01 | J. Appel, A. MacRae, A. Lvovsky |
| Photons as quasi-charged particles University of Calgary | Publication | 2008-01-01 | K. -. Marzlin, J. Appel, A. Lvovsky |
| Matched slow pulses using double electromagnetically induced transparency University of Calgary | Publication | 2008-01-01 | A. MacRae, G. Campbell, A. Lvovsky |
| Quantum tomography of the single-photon state generated by down conversion in a periodically poled KTP Crystal University of Calgary | Publication | 2009-01-01 | N. Jain, S. -. Youn, A. Lvovsky |
| Slow photons as charged Quasi-ParticlesRecently we have proposed the method of Raman Adiabatic Transfer of Optical States (RATOS)
to manipulate the optical state of light. A four-level atomic medium in double-Lambda configuration
is interacting with two pump fields and a signal photon with very slow group velocity. An
adiabatic change in time of the pump fields can then generate a slow photon in a superposition
of different frequencies. Here we theoretically analyze the influence of an adiabatic change in
the spatial form of the pump fields. We demonstrate that the signal photon then behaves like a
charged quasi-particle: in paraxial approximation its dynamics is governed by a Schroedingerlike
equation that includes a scalar and a vector potential whose form is determined by the
shape of the pump fields. We suggest pump field configurations that generate potentials corresponding
to a constant electric and a constant magnetic field. In both cases the center of a
Gaussian signal pulse follows the trajectory of corresponding classical point particles. In the
case of a quasi-magnetic field the dispersion of the pulse is reduced. We give an intuitive interpretation
of this effect, which may have application as a waveguide of light inside an atomic
vapor. Furthermore, we devise a scheme of pump fields that generates a vector University of Calgary | Presentation | 2007-09-04 | K. Marzlin, J. Appel, A. Lvovsky |
| Quantum tomography of the single photon state generated by down-conversion in a periodically poled KTP crystal University of Calgary | Presentation | 2008-08-23 | S. Youn, N. Jain, A. Lvovsky |
| Slow photons as charged quasi-particles, and photonic Aharonov-Bohm effectRecently we have proposed the method of Raman Adiabatic
Transfer of Optical States (RATOS) to manipulate the
optical state of light [1]. In this method a four-level atomic
medium in double-Lambda configuration is interacting with two pump
fields and a signal photon, which can be in a superposition of
two modes with different frequencies. Depending on the
intensity of the pump fields, only a particular superposition
will experience electromagnetically induced transparency and thus
can be slowed down. An adiabatic change in time of the pump fields can
then change this superposition dynamically.
Here we theoretically analyze the influence of an adiabatic change
in the spatial form of the pump fields. We demonstrate that the
signal photon then behaves like a charged quasi-particle: in
paraxial approximation its dynamics is governed by a Schroedinger-like
equation that includes a scalar and a vector quasi-potential whose
form is determined by the shape of the pump fields. We suggest
pump field configurations that generate potentials corresponding
to a constant electric and a constant magnetic quasi-field and show
that the magnetic quasi-field suppresses spatial dispersion
of the signal photon. Furthermore we devise a scheme of pump fields
that generates a vector potential of Aharonov-Bohm type.
This induces a topological phase shift on the signal field.
[1] J. Appel, K.-P. Marzlin and A.I. Lvovsky, Phys. Rev. A 73, 013804 (2006). University of Calgary | Presentation | 2007-06-19 | K. Marzlin, J. Appel, A. Lvovsky |
| Slow photons as charged quasi-particles, and photonic Aharonov-Bohm effectRecently we have proposed the method of Raman Adiabatic
Transfer of Optical States (RATOS) to manipulate the
optical state of light. A four-level atomic medium in
double-$\Lambda$ configuration is interacting with two pump
fields and a signal photon with very slow group velocity.
An adiabatic change in time of the pump fields can then
generate a slow photon in a superposition of different frequencies.
Here we theoretically analyze the influence of an adiabatic change
in the spatial form of the pump fields. We demonstrate that the
signal photon then behaves like a charged quasi-particle: in
paraxial approximation its dynamics is governed by a
Schr\"odinger-like equation that includes a scalar and a vector
potential whose form is determined by the shape of the pump fields.
We suggest pump field configurations that generate potentials
corresponding to a constant electric and a constant magnetic field.
Furthermore we devise a scheme of pump fields that generates a vector
potential of Aharonov-Bohm type which induces a topological phase shift
for slow photons. University of Calgary | Presentation | 2007-06-09 | K. Marzlin, J. Appel, A. Lvovsky |
| Continuous-variable experiments with a nonlocal single photon A two-mode optical qubit is generated when a single photon from a parametric down conversion source entangles itself with a vacuum on a beam splitter. We have characterized this dual-rail state by means of homodyne tomography. From the quadrature statistics, applying the maximum likelihood method, density matrix is calculated which extends over the entire Hilbert space and thus reveals, for the first time, complete information about the qubit as a state of the electromagnetic field. A nonlocal nature of the reconstructed state is shown by a violation of the Bell inequality for the experimental data converted to a dichotomic format. This experiment can be interpreted as remote preparation of an arbitrary single-mode optical qubit. By measuring a quadrature on one of the spatial modes of the entangled state, we project the other mode onto a coherent superposition of the single-photon and vacuum states. Surprisingly, the state obtained in this manner can be of higher purity than the single-photon resource we started with.
University of Calgary | Presentation | 2004-07-20 | S. Babichev, J. Appel, A. Lvovsky |
| Demonstration of double electromagnetically induced transparency in a hot atomic vapourWe report demonstration of double electromagnetically-induced transparency in a hot rubidium-87 vapor: two transparency windows appear simultaneously on |5S_{1/2},F=1> -> | 5P_{1/2},F=2> and $|5S_{1/2},F=2> -> | 5P_{1/2},F=2> when a single control field is applied. We have been able to simultaneously slow down two optical pulses resonant with these transitions. By switching the control field, we have demonstrated simultaneous storage of these pulses. University of Calgary | Presentation | 2008-05-30 | A. MacRae, G. Campbell, A. Lvovsky |
| Engineering of optical states from an atomic source University of Calgary | Presentation | 2011-11-10 | A. MacRae, T. Brannan, A. Lvovsky |
| Towards quantum engineering University of Calgary | Presentation | 2012-01-04 | A. MacRae, T. Brannan, A. Lvovsky |
| Quantum process tomography of photon addition and subtraction University of Calgary | Presentation | 2012-06-14 | R. Kumar, E. Barrios, A. Lvovsky |
| Characterization of a high efficiency optical memory for the storage of quantum light statesWe have developed a coherent optical storage device based on a Gradient Echo Memory scheme showing efficiencies of above 65\%. The memory is realized in a warm vapor of 87Rb atoms utilizing a Λ-type energy level scheme. We use a co-propagating, co-rotating circular polarized pump beam coupled with pulsed coherent states to create an off-resonant Raman absorption line suitable for storage. Through sufficient filtration of the strong pump field, the stored light pulse is retrieved after a desired time and subjected to time-domain homodyne tomography. By repeating this sequence on an ensemble of 50 000 identical coherent states we gain enough information to completely reconstruct the quantum state of light retrieved from the memory. Furthermore, by repeating this characterization for a set of coherent states with at sufficient range of amplitudes we can completely characterize the memory process itself. This is possible by implementing a method devised by our group called coherent state Quantum Process Tomography which also has the capability to predict how well the memory will perform on any arbitrary quantum input state. We show our current storage efficiencies and what needs to be further done to demonstrate a true high efficiency, quantum optical memory. University of Calgary | Presentation | 2012-06-07 | C. Kupchak, R. Thomas, A. Lvovsky |
| Characterization of high efficiency quantum memory University of Calgary | Presentation | 2012-06-14 | C. Kupchak, R. Thomas, A. Lvovsky |
| Evanescent EIT and Goos-Hanchen shifts University of Calgary | Presentation | 2012-05-24 | C. Kupchak, R. Thomas, A. Lvovsky |
| Characterization of a high efficiency optical memory for the storage of quantum light states University of Calgary | Presentation | 2012-07-25 | C. Kupchak, R. Thomas, A. Lvovsky |
| A monolithic filter cavity for single-photon experiment in atomic physics University of Calgary | Presentation | 2012-06-14 | P. Palittapongarnpim, A. MacRae, A. Lvovsky |
| Narrowband Photon from an Atomic SourceWe demonstrate efficient generation of narrow-bandwidth photon superposition states. Since the heralded states stem from a transient collective spin excitation in the atomic ensemble, this work allows the engineering of arbitrary collective atomic excitation states. University of Calgary | Presentation | 2012-10-17 | A. MacRae, T. Brannan, A. Lvovsky |
| Electronic noise in optical homodyne tomography University of Calgary | Publication | 2007-03-01 | J. Appel, D. Hoffman, E. Figueroa, A. Lvovsky |
| Diluted maximum-likelihood algorithm for quantum tomography University of Calgary | Publication | 2007-04-01 | J. Řeháček, Z. Hradil, E. Knill, A. Lvovsky |
| Memory for Light as a Quantum Process University of Calgary | Publication | 2009-05-01 | M. Lobino, C. Kupchak, E. Figueroa, A. Lvovsky |
| Adiabatic frequency conversion of optical information in atomic vapor University of Calgary | Publication | 2007-01-01 | F. Vewinger, J. Appel, E. Figueroa, A. Lvovsky |
| Quantum-optical state engineering up to the two-photon level University of Calgary | Publication | 2010-02-01 | E. Bimbard, N. Jain, A. MacRae, A. Lvovsky |
| A bridge between the single-photon and squeezed-vacuum states University of Calgary | Publication | 2010-01-01 | N. Jain, S. R. Huisman, E. Bimbard, A. Lvovsky |
| Transverse multimode effects on the performance of photon-photon gates University of Calgary | Publication | 2011-02-01 | B. He, A. MacRae, Y. Han, A. Lvovsky, C. Simon |
| Tomography of a High-Purity Narrowband Photon from a Transient Atomic Collective Excitation University of Calgary, University of Alberta | Publication | 2012-07-01 | A. MacRae, T. Brannan, R. Achal, A. Lvovsky |
| Experimental Characterization of Bosonic Creation and Annihilation Operators University of Calgary | Publication | 2013-03-01 | R. Kumar, E. Barrios, C. Kupchak, A. Lvovsky |
| Generation and tomography of arbitrary optical qubits using transient collective atomic excitations University of Calgary | Publication | 2014-01-01 | T. Brannan, Z. Qin, A. MacRae, A. Lvovsky |
| Quantum vampire: collapse-free action at a distance by the photon annihilation operator University of Calgary | Publication | 2015-01-01 | I. A. Fedorov, A. E. Ulanov, Y. Kurochkin, A. Lvovsky |
| Generation and tomography of arbitrary qubit states using transient collective atomic excitations University of Calgary | Publication | 2014-01-01 | T. Brannan, Z. Qin, A. MacRae, A. Lvovsky |
| Observation of electromagnetically induced transparency in evanescent fields University of Calgary | Publication | 2013-01-01 | R. Thomas, C. Kupchak, G. S. Agarwal, A. Lvovsky |
| A bridge between the single-photon and squeezed-vacuum state University of Calgary | Publication | 2010-01-01 | N. Jain, S. R. Huisman, E. Bimbard, A. Lvovsky |
| Adiabatic frequency conversion of quantum optical information in atomic vapor University of Calgary | Publication | 2007-01-01 | F. Vewinger, J. Appel, E. Figueroa, A. Lvovsky |
| Decoherence of electromagnetically-induced transparency in atomic vapor University of Calgary | Publication | 2006-01-01 | E. Figueroa, F. Vewinger, J. Appel, A. Lvovsky |
| Simultaneous slow light pulses with matched group velocities via double-EIT University of Calgary | Publication | 2009-01-01 | A. MacRae, G. Campbell, A. Ordog, A. Lvovsky |
| Characterization of atomic coherence decay for storage of light experiments University of Calgary | Presentation | 2006-08-14 | E. Figueroa, F. Vewinger, J. Appel, A. Lvovsky, G. Günter |
| Giant optical nonlinearities using double electromagnetically induced transparency in Rubidium University of Calgary | Presentation | 2007-09-26 | A. MacRae, Z. Wang, K. Marzlin, A. Lvovsky |
| Characterization of decoherence in electromagnetically induced transparency for applications in storage of lightElectromagnetically-induced transparency (EIT) has many applications in quantum information, particularly in quantum memory for light [1]. These applications require understanding of the phenomena responsible for decoherence in such processes. Insight into this question can be gained by measuring the width of the EIT resonance as a function of the pump field intensity. We report characterization of EIT resonances in the D1 line of Rb 87 under various experimental conditions. The dependence of the EIT linewidth on the power of the control field was investigated, at various temperatures, for lambda level configurations associated with different hyperfine levels of the atomic ground state as well as magnetic sublevels of the same hyperfine level. Strictly linear behavior was observed in all cases. Our results were inconsistent with a widely accepted theory where population exchange between the ground levels is assumed to be the main decoherence mechanism [2]. We therefore formulated a new theory assuming pure dephasing (decay of off-diagonal matrix elements) as the new mechanism. Our data shows this theory to be in good agreement with our experiments. 1. D. F. Phillips, A. Fleischhauer, A. Mair, R. L. Walsworth, and M. D. Lukin, Phys. Rev. Lett. \textbf{86}, 783 (2001). 2. H. Lee, Y. Rostovtsev, C. J. Bednar, and A. Javan, Appl. Phys. B \textbf{76}, 33 (2003).
University of Calgary | Presentation | 2007-06-07 | E. Figueroa, J. Appel, F. Vewinger, A. Lvovsky |
| Spatial and temporal characterization of a Bessel beam produced using a conical mirror University of Calgary | Presentation | 2008-08-21 | K. Kuntz, B. Braverman, M. Lobino, A. Lvovsky |
| Electromagnetically induced transparency using evanescent fields in warm atomic vapour University of Calgary | Presentation | 2012-07-23 | R. Thomas, C. Kupchak, A. G. Agarwal, A. Lvovsky |
| Quantum vampire: action at a distance of the photon annihilation operator University of Calgary | Presentation | 2014-10-29 | A. I. Fedorov, E. A. Ulanov, Y. Kurochkin, A. Lvovsky |
| Routing of optical states by atomic media University of Calgary | Presentation | 2006-05-21 | J. Appel, E. Figueroa, F. Vewinger, A. Lvovsky |
| Electronic noise in optical homodyne tomographyIn experiments on homodyne tomography of light, the electronic noise of the detector often prevents the observation of the fine details of the quantum state's marginal distributions. We have shown that the noise contribution from the detector can be modeled by an equivalent inefficiency arising due to optical loss. We confirm this result using a non-classical squeezed light produced with an optical parametric amplifier.
University of Calgary | Presentation | 2007-06-08 | D. Hoffman, J. Appel, E. Figueroa, A. Lvovsky |
| Double electromagnetically-induced transparency in rubidium vaporWe report demonstration of double electromagnetically-induced transparency in a hot rubidium-87 vapor: two transparency windows appear simultaneously on | 5S_{1/2},F=1> to | 5P_{1/2},F=2> and |5S_{1/2},F=2> to |5P_{1/2},F=2> when a single control field is applied. We have been able to simultaneously slow down two optical pulses resonant with these transitions. By switching the control field, we have demonstrated simultaneous storage of these pulses. This scheme can be applied to achieve optical nonlinearities in the pulsed regime at light levels as low as a few photons per atomic cross section.
University of Calgary | Presentation | 2008-06-11 | A. MacRae, G. Campbell, K. Marzlin, A. Lvovsky |
| Electromagnetically-induced transparency and squeezed lightWe study electromagnetically-induced transparency (EIT) as a tool for slowing down and storing squeezed light. The experiments are conducted in rubidium vapour, and the squeezed vacuum state is prepared by means of an optical parametric amplifier. Full homodyne tomography of the squeezed vacuum pulse before and after the interaction with the EIT cell provides insight into the phenomena that degrade the storage fidelity.
University of Calgary | Presentation | 2007-08-22 | J. Appel, E. Figueroa, D. Korystov, A. Lvovsky |
| Process tomography of quantum-optical memory University of Calgary | Presentation | 2009-01-05 | M. Lobino, C. Kupchak, E. Figueroa, A. Lvovsky |
| Double electromagnetically induced transparency in rubidium vapour University of Calgary | Presentation | 2009-08-06 | A. MacRae, G. Campbell, A. Ordog, A. Lvovsky |
| Single-mode quantum engineering of light University of Calgary | Presentation | 2010-07-09 | E. Bimbard, N. Jain, A. MacRae, A. Lvovsky |
| Quantum technology of light at the two-photon level University of Calgary | Presentation | 2010-05-25 | E. Bimbard, N. Jain, A. MacRae, A. Lvovsky |
| Electromagnetically induced transparency with evanescent fields University of Calgary | Presentation | 2012-07-25 | R. Thomas, C. Kupchak, A. G. Agarwal, A. Lvovsky |
| Towards engineering arbitrary superpositions of collective spin excitations University of Calgary, University of Alberta | Presentation | 2012-07-23 | T. Brannan, A. MacRae, R. Achal, A. Lvovsky |
| Tomography of single photons and qubits generated by atoms University of Calgary, University of Alberta | Presentation | 2012-07-04 | A. MacRae, T. Brannan, R. Achal, A. Lvovsky |
| Generation of arbitrary quantum states from atomic ensembles University of Calgary, University of Alberta | Presentation | 2012-06-11 | A. MacRae, T. Brannan, R. Achal, A. Lvovsky |
| Electromagnetically induced transparency with evanescent optical fields University of Calgary | Presentation | 2012-06-12 | R. Thomas, C. Kupchak, A. G. Agarwal, A. Lvovsky |
| Tomography of a high-purity narrowband photon from four-wave mixing in atomic vapourMuch work has been done in recent years to develop interesting quantum states in the optical regime. A natural step forward would be to extend our quantum state engineering abilities to collective spin excitations (CSE’s) in hot atomic vapour. Such an extension could find applications in quantum memory, long distance quantum communication, quantum logic gates, and quantum metrology. We demonstrate a setup that serves as a high quality single photon source and a first step towards quantum state engineering of arbitrary states in CSE’s.
We use four-wave mixing in a hot atomic vapour cell to create a two-mode squeezed state, similar to parametric down conversion. Heralding on a single photon event in one channel yields a high purity narrow-bandwidth single photon in the other channel. Employing optical homodyne tomography, we reconstruct the density matrix of the generated photon and observe a Wigner function reaching the zero value without correcting for inefficiencies. The intrinsic narrow bandwidth and high production rate of our system result in a high spectral brightness source. Since these photons are also naturally resonant to atomic transitions, our source is attractive for applications in light-atom interfacing.
Moving to the pulsed regime would allow for time separated events of CSE creation and optical readout, akin to the well-known DLCZ scheme. Conditional measurements during the write phase prepare the CSE in an arbitrary superposition state, which can then be read out optically and measured via homodyne tomography.
University of Calgary, University of Alberta | Presentation | 2012-08-16 | T. Brannan, A. MacRae, R. Achal, A. Lvovsky |
| Multimode quantum black-box characterization University of Calgary | Presentation | 2014-05-30 | A. I. Fedorov, K. A. Fedorov, Y. Kurochkin, A. Lvovsky |
| Universal homodyne detector with high bandwidthWir stellen einen Homodyne-Detektor mit einer Bandbreite >
200 MHz vor. Ein Ti:Sa Laser (Coherent Mira, 76 MHz Pulswiederholrate)
dient als Lokaloszillator in einem balancierten Detektionsschema. Die
Pulse werden mittels zweier vorgespannter Si-PIN Fotodioden detektiert,
deren Differenzstrom in einem als Transimpedanzwandler geschalteten
Operationsverst¨arker verst¨arkt wird. Bei einer Leistung von 10 mW des
Lokaloszillators liegt das optische Schrotrauschen bis zu 15 dB ¨uber dem
elektronischen Rauschen des Detektors. Die hohe Bandbreite des Detektors
erlaubt Messungen sowohl im Frequenz- als auch im Zeitraum bei
der vollen Pulswiederholrate des Lokaloszillators, z.B. f¨ur Quantenkommunikation
mit kontinuierlichen Variablen. University of Calgary | Presentation | 2006-03-13 | F. Vewinger, S. Babichev, J. Appel, A. Lvovsky |
| Adiabatic transfer of quantum optical information in atomic vaporWe demonstrate a quantum communication protocol (RATOS) that enables frequency conversion and routing of quantum optical information in an adiabatic and robust way. The protocol is based on EIT in systems with multiple excited levels. Article not available. University of Calgary | Presentation | 2006-10-08 | E. Figueroa, F. Vewinger, J. Appel, A. Lvovsky |
| Characterization of atomic coherence decay for the storage of light University of Calgary | Publication | 2006-08-01 | E. Figueroa, F. Vewinger, J. Appel, G. Günter, A. Lvovsky |
| Quantum Memory for Squeezed Light University of Calgary | Publication | 2008-03-01 | J. Appel, E. Figueroa, D. Korystov, M. Lobino, A. Lvovsky |
| Optomechanical Micro-Macro Entanglement University of Calgary | Publication | 2014-02-01 | R. Ghobadi, S. Kumar, B. Pepper, D. Bouwmeester, A. Lvovsky, C. Simon |
| Classical and quantum fingerprinting with shared randomness and one-sided error University of Calgary | Publication | 2005-05-01 | R. T. Horn, A. Scott, J. Walgate, R. Cleve, A. Lvovsky, B. C. Sanders |
| A peek into a quantum black box University of Calgary | Presentation | 2009-07-08 | M. Lobino, C. Kupchak, E. Figueroa, J. Appel, A. Lvovsky |
| Deterministic conditional phase gate with Rydberg atomsOne of the most promising ways to implement deterministic quantum conditional gate between individual photons is to use the interaction between the large dipole moments of Rydberg polaritons. The multimode character of pulses imposes constraints on implementation of high fidelity quantum gates. To overcome this problem, we have shown that parallel orientation of the dipoles results in optimum fidelity. Additionally, we also have obtained the analytical form for both the induced phase and the fidelity between polaritons for the case that the length of the interaction region is much greater than the size of the polariton wave packets. We also present the advantages of this proposal over previous approaches.
University of Calgary | Presentation | 2011-06-16 | H. Kaviani, B. He, A. MacRae, W. Jiang, A. Lvovsky, C. Simon |
| Routing of optical states by atomic mediaElectromagnetically induced transparency (EIT) is a quantum interference
effect, in which a weak signal light field and a stronger control field
drive atomic transitions with a common excited state. The quantum
interference between both light-atom interactions leads to strong
dispersion which causes phenomena such as slowdown and stopping of
light and can be used for enhanced nonlinear interaction.
We extended the standard quantum theory of EIT to accommodate for
multiple excited levels and show experimentally that a transfer of
optical quantum states between different signal modes can be
implemented by an adiabatic change of the control fields.
Raman adiabatic transfer of optical states resembles stimulated Raman
adiabatic passage (STIRAP) but applies to optical rather than atomic
states. It can be used to route and distribute optically encoded
information in classical and quantum communication.
We performed experiments using the hyperfine levels of Rb87 atoms
at the D1 line: First, a signal pulse (resonant to the F=1,
F'=1 transition) was placed into the cell under EIT conditions created
by a control laser (resonant to F=2, F'=1). Then adiabatically this
laser is switched off while another control laser (resonant to F=2,
F'=2) is switched on. This procedure transfers the information carried
by the state of the original signal pulse to the optical mode resonant
with the F=1, F'=2 transition. University of Calgary | Presentation | 2006-05-02 | J. Appel, E. Figueroa, F. Vewinger, K. Marzlin, A. Lvovsky |
| Polarization squeezing in atomic Rubidium vapourRecently there has been debate regarding the possibility of using polarization self-rotation (PSR) in a thermal vapour cell as a mechanism for generating a squeezed vacuum state [1,2]. It has been claimed that the squeezing produced by this method is overwhelmed by atomic noise in the thermal vapour [2]. We present a new experimental study on the possibility to generate squeezing in this system and theoretical results that highlight the importance of the atomic ground state decoherence. \newline \newline [1] J. Ries, B. Brezger and A. I. Lvovsky, Pys. Rev. A 68, 025801 (2003). \newline [2] M. T. L. Hsu, G. Hetet, A. Peng, C. C. Harb, H.-A. Bachor, M. T. Johnsson, J. J. Hope, P. K. Lam, A. Dantan, J. Cviklinski, A. Bramati and M. Pinard, Phys. Rev. A 73, 023806 (2006). University of Calgary | Presentation | 2007-06-08 | G. Campbell, C. Healey, J. Appel, K. Marzlin, A. Lvovsky |
| Experimental Raman adiabatic transfer of optical states in rubidiumAn essential element of a quantum optical communication network is a tool for transferring and/or distributing quantum information between optical modes (possibly of different frequencies) in a loss- and decoherence-free fashion. We present a theory [1] and an experimental demonstration [2] of a protocol for routing and frequency conversion of optical quantum information via electromagnetically-induced transparency in an atomic system with multiple excited levels. Transfer of optical states between different signal modes is implemented by adiabatically changing the control fields. The proof-of-principle experiment is performed using the hyperfine levels of the rubidium D1 line. [1] F. Vewinger, J. Appel, E. Figueroa, A. I. Lvovsky, quant-ph/0611181 [2] J. Appel, K.-P. Marzlin, A. I. Lvovsky, Phys. Rev. A \\textbf{73}, 013804 (2006) University of Calgary | Presentation | 2007-06-08 | J. Appel, E. Figueroa, F. Vewinger, K. Marzlin, A. Lvovsky |
| Interfacing quantum light with atoms using electromagnetically-induced transparency University of Calgary | Presentation | 2008-08-12 | E. Figueroa, J. Appel, D. Korystov, M. Lobino, A. Lvovsky |
| Electromagnetically induced transparency and squeezed light University of Calgary | Presentation | 2008-05-22 | M. Lobino, J. Appel, E. Figueroa, D. Korystov, A. Lvovsky |
| Do we need quantum light to test quantum memory? University of Calgary | Presentation | 2009-06-10 | M. Lobino, C. Kupchak, E. Figueroa, J. Appel, A. Lvovsky |
| Single photons generated by atoms University of Calgary, University of Alberta | Presentation | 2012-05-23 | A. MacRae, T. Brannan, P. Palittapongarnpim, R. Achal, A. Lvovsky |
| Measuring the temporal wavefnction of a photonHomodyne tomography provides information about the signal state of the electromagnetic field in the mode of the local oscillator. If the signal state is known to be the signal photon, the mode of that photon can be determined by searching for the temporal shape of the local oscillator pulse such that the observed single-photon efficiency is maximized. However, if the bandwidth of the temporal mode of the photon is sufficiently narrow in comparison with those of the detector and the acquisition system, the same task can be solved with a continuous local oscillator, thereby greatly simplifying the experimental procedure. Complete information about the mode can be obtained from the autocorrelation statistics of the homodyne photocurrent acquired at several different local oscillator frequencies. We present a theory and experiment to demonstrate the capabilities of this technique. A heralded single photon is obtained from a pair generated via four-wave mixing in an atomic vapor and the required bandwidth is achieved by spectral filtering of the trigger channel by means of a narrowband optical cavity. University of Calgary | Presentation | 2013-07-18 | T. Brannan, Z. Qin, A. MacRae, A. Lezama, A. Lvovsky |
| Raman adiabatic transfer of optical statesElectromagnetically induced transparency (EIT) is a quantum interference effect occurring when a weak signal light field and a stronger control field interact in atomic ensembles with a lambda-shaped energy level configuration. This effect attracts great interest due to its possible applications in non-linear optics and quantum information processing.
The range of possible applications of EIT extends further in lambda-systems with multiple excited levels. In this work, we show experimentally that by an adiabatic change of the control fields, a transfer of optical states between different signal modes can be implemented [1]. This procedure resembles stimulated Raman adiabatic passage (STIRAP) but applies to optical rather than atomic states. It can be useful for routing and distribution of optically encoded information in classical and quantum communication.
The experiments were performed using the hyperfine levels of Rb 87 atoms at the D1 line. First, we placed a signal pulse (resonant to the F=1, F’=1 transition) into the cell under EIT conditions created by a control laser (resonant to F=2, F’=1). This laser is adiabatically switched off while another control laser (resonant to F=2, F’=2) is switched on. The information carried by the state of the original signal pulse is transferred to the optical mode resonant with the F=1, F’=2 transition. Transfer efficiencies above 50 % have been achieved.
While the experiment was conducted with classical light pulses, the implemented procedure can be extended to nonclassical light [1] and thus can be used for a variety of applications in quantum information processing.
1. J. Appel, K. –P. Marzlin and A. I. Lvovsky. PRA 73, 013804 (2006)
* This work is being supported by NSERC, CFI, AIF, CIAR
University of Calgary | Presentation | 2006-06-12 | E. Figueroa, J. Appel, G. Günter, K. Marzlin, A. Lvovsky |
| Quantum process tomography with coherent states University of Calgary | Publication | 2011-01-01 | S. Rahimi-Keshari, A. Scherer, A. Mann, A. Rezakhani, A. Lvovsky |
| Quantum process tomography with coherent states, New Journal of Physics University of Calgary | Publication | 2011-01-01 | S. Rahimi-Keshari, A. Scherer, A. Mann, A. Rezakhani, A. Lvovsky, B. C. Sanders |
| Versatile wideband balanced detector for quantum optical homodyne tomography University of Calgary | Publication | 2012-11-01 | R. Kumar, E. Barrios, A. MacRae, E. Cairns, E. H. Huntington, A. Lvovsky |
| Spatial and temporal characterization of a Bessel beam produced using a conical mirror University of Calgary | Publication | 2009-01-01 | K. Kuntz, B. Braverman, S. -. Youn, M. Lobino, S. Youn, A. Lvovsky |
| Electromagnetically-induced transparency and squeezed light University of Calgary | Publication | 2009-01-01 | E. Figueroa, J. Appel, C. Kupchak, M. Lobino, D. Korystov, A. Lvovsky |
| Decoherence in electromagnetically-induced transparency University of Calgary | Presentation | 2006-02-25 | J. Appel, E. Figueroa, F. Vewinger, G. Günter, K. Marzlin, A. Lvovsky |
| Controlling light by electromagnetically-induced transparency University of Calgary | Presentation | 2006-05-07 | J. Appel, E. Figueroa, F. Vewinger, G. Günter, K. Marzlin, A. Lvovsky |
| Giant optical nonlinearities between two matched pulsesOne of the primary limitations of nonlinear optics is that relatively high intensities are needed to produce a noticeable effect. However, in an atomic system with electromagnetically induced transparency (EIT) it is possible to observe nonlinearities at light levels as low as a few photons per atomic cross section [1]. Implementation of the EIT-based nonlinearity with pulsed light may however be challenging as it requires the interacting pulses to propagate at equal group velocities. Recently, a scheme satisfying this requirement was proposed which employs double EIT in atomic Rubidium-87 [2]. We report on our recent progress towards experimentally realizing this scheme. We have successfully demonstrated a double EIT system in which two separate pulses may be simultaneously slowed or stored. By applying a large, homogenous magnetic field across the atomic vapor, thus splitting the atomic levels, we create a large nonlinear interaction in the form of XPM. *References: [1]: H. Schmidt, and V. Imamoglu, Optics Letters 21 23 1996 [2]: Z.B. Wang, K.P. Marzlin, B.C. Sanders, Phys. Rev. Lett. 97 06, 2006 University of Calgary | Presentation | 2008-05-30 | A. MacRae, G. Campbell, Z. Wang, K. Marzlin, B. C. Sanders, A. Lvovsky |
| Electromagnetically-induced transparency and squeezed light University of Calgary | Presentation | 2008-08-20 | E. Figueroa, J. Appel, D. Korystov, M. Lobino, C. Kupchak, A. Lvovsky |
| Quantum optical state engineering at the few photon level University of Calgary | Presentation | 2010-05-24 | N. Jain, E. Bimbard, S. R. Huisman, S. Youn, A. MacRae, A. Lvovsky |
| Adiabatic transfer of quantum optical information by means of electromagnetically-induced transparency University of Calgary | Presentation | 2006-07-25 | J. Appel, F. Vewinger, E. Figueroa, G. Günter, K. Marzlin, A. Lvovsky |
| Towards storage of squeezed light by electromagnetically induced transparencyElectromagnetically induced transparency (EIT) is a quantum interference effect, in which a strong control laser beam changes a medium's linear dispersion and absorption in such a way that a weak signal beam travels without absorption and its group velocity is greatly reduced. Theoretical models and recent experiments predict that adiabatic switching of the control field while the signal is inside the medium reversibly maps the signal quantum state to the states of the irradiated atoms. We report on our recent progress in storing and retrieving a squeezed optical state by adiabatic conversion to a collective coherent superposition of the hyperfine ground levels of the D1 transition in rubidium-87. A bright narrowband source of nonclassical light for interaction with atoms has been constructed based on an optical parametric amplifier featuring a periodically poled KTP crystal. Ultrafast lossless switching allows us to generate 1 $\mu$s pulses of up to 3 dB squeezed vacuum resonant to the EIT transparency window. We investigate the transmission and storage of these states under EIT conditions by homodyne tomography.
University of Calgary | Presentation | 2007-06-09 | J. Appel, E. Figueroa, F. Vewinger, D. Korystov, G. Günter, A. Lvovsky |
| A continuous-variable approach to process tomographyWe propose and demonstrate experimentally a technique for estimating quantum-optical processes in the continuous-variable domain. The process data is determined by applying the process to a set of coherent states and measuring the output. The process output for an arbitrary input state can then be obtained from its Glauber-Sudarshan expansion. Although such expansion is generally singular, it can be arbitrarily well approximated with a regular function. University of Calgary | Presentation | 2008-08-26 | M. Lobino, E. Figueroa, D. Korystov, C. Kupchak, B. C. Sanders, A. Lvovsky |
| Measuring the temporal wave function of a photon University of Calgary | Presentation | 2014-05-29 | Z. Qin, A. Prasad, T. Brannan, A. MacRae, A. Lezama, A. Lvovsky |
| Raman adiabatic transfer of optical statesWir pr¨asentieren ein Protokoll zum Transfer von Quantenzust¨anden
zwischen zwei optischenModen basierend auf elektromagnetisch induzierter
Transparenz. Wird ein metastabiler Zustand durch zwei (klassische)
Kontrollfelder an zwei angeregte Zust¨ande gekoppelt, welche wiederum
mittels zweier (quantisierter) Signalfelder an einen weiteren metastabilen
Zustand gekoppelt sind (Multi- Konfiguration), so laesst sich durch
die geeignete Wahl der Kontrollelder der Quantenzustand eines Signalfeldes
adiabatisch auf die zweite Signalmode ¨ubertragen. Wir pr¨asentieren
ein theoretisches Modell, welches den Transfer beschreibt, sowie erste
Ergebnisse auf dem Weg zur experimentellen Implementierung in Rubidiumdampf. University of Calgary | Presentation | 2006-03-13 | F. Vewinger, J. Appel, E. Figueroa, G. Günter, K. Marzlin, A. Lvovsky |
| Towards storage of non-classical light using electromagnetically induced transparencyElectromagnetically induced transparency (EIT) is a quantum interference effect in which a strong control laser beam changes a medium's linear dispersion and absorption allowing a weak signal beam to travel without absorption and with its group velocity greatly reduced. This allows the storage of quantum information on the irradiated atoms. We report on our recent progress in storing and retrieving a squeezed optical state using hyperfine ground levels of the D1 transition in rubidium-87. A narrowband source of nonclassical light for interaction with atoms has been constructed based on parametric amplification featuring a periodically poled KTP crystal. Ultrafast lossless switching allows us to generate 1 us pulses of up to 3 dB squeezed vacuum resonant to the EIT transparency window. We investigate the transmission and storage of these states under EIT conditions by homodyne tomography. University of Calgary | Presentation | 2007-08-11 | E. Figueroa, J. Appel, F. Vewinger, D. Korystov, G. Günter, A. Lvovsky |
| Instant single-photon Fock state tomography University of Calgary | Publication | 2009-01-01 | S. R. Huisman, N. Jain, S. Babichev, F. Vewinger, A. -. Zhang, S. -. Youn, A. Lvovsky |
| Coherent-state quantum process tomography University of Calgary | Presentation | 2010-08-05 | M. Lobino, C. Kupchak, R. Kumar, E. Barrios, A. Hendriks, E. Figueroa, A. Lvovsky |
| Quantum-optical process tomography using coherent states University of Calgary | Presentation | 2010-07-19 | M. Lobino, D. Korystov, C. Kupchak, E. Figueroa, R. Kumar, E. Barrios, S. Rahimi-Keshari, A. Scherer, B. C. Sanders, A. Lvovsky |
