301
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Pestov D, Zhi M, Sariyanni ZE, Kalugin NG, Kolomenskii AA, Murawski R, Paulus GG, Sautenkov VA, Schuessler H, Sokolov AV, Welch GR, Rostovtsev YV, Siebert T, Akimov DA, Graefe S, Kiefer W, Scully MO. Visible and UV coherent Raman spectroscopy of dipicolinic acid. Proc Natl Acad Sci U S A 2005; 102:14976-81. [PMID: 16217021 PMCID: PMC1257716 DOI: 10.1073/pnas.0506529102] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We use time-resolved coherent Raman spectroscopy to obtain molecule-specific signals from dipicolinic acid (DPA), which is a marker molecule for bacterial spores. We use femtosecond laser pulses in both visible and UV spectral regions and compare experimental results with theoretical predictions. By exciting vibrational coherence on more than one mode simultaneously, we observe a quantum beat signal that can be used to extract the parameters of molecular motion in DPA. The signal is enhanced when an UV probe pulse is used, because its frequency is near-resonant to the first excited electronic state of the molecule. The capability for unambiguous identification of DPA molecules will lead to a technique for real-time detection of spores.
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Affiliation(s)
- Dmitry Pestov
- Institute for Quantum Studies, Texas A&M University, College Station, TX 77843-4242, USA
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302
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Cheng J, Han S, Yan Y. Nonlinear propagation of ultraslow pulses in media with electromagnetically induced transparency. OPTICS LETTERS 2005; 30:2638-40. [PMID: 16208925 DOI: 10.1364/ol.30.002638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The nonlinear behavior of a probe pulse propagating in a medium with electromagnetically induced transparency is studied both numerically and analytically. A new type of nonlinear wave equation is proposed in which the noninstantaneous response of nonlinear polarization is treated properly. The resulting nonlinear behavior of the propagating probe pulse is shown to be fundamentally different from that predicted by the simple nonlinear Schrödinger-like wave equation that considers only instantaneous Kerr nonlinearity.
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Affiliation(s)
- Jing Cheng
- Key Laboratory for Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.
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303
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Yang Q, Seo JT, Tabibi B, Wang H. Slow light and superluminality in Kerr media without a pump. PHYSICAL REVIEW LETTERS 2005; 95:063902. [PMID: 16090955 DOI: 10.1103/physrevlett.95.063902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2004] [Indexed: 05/03/2023]
Abstract
Subluminal and superluminal propagation of a light pulse in Kerr materials has been investigated. Group velocities as slow as much less than 1 mm per second to as fast as negative several thousands meters per second can easily be obtained in the Kerr medium, which possesses a large nonlinear refractive index and long relaxation time, such as Cr3+-doped alexandrite, ruby, and GdAlO3. The physical mechanism is the strong highly dispersive coupling between different frequency components of the pulse.
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Affiliation(s)
- Qiguang Yang
- Department of Physics, Hampton University, Hampton, Virginia 23668, USA.
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304
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Longdell JJ, Fraval E, Sellars MJ, Manson NB. Stopped light with storage times greater than one second using electromagnetically induced transparency in a solid. PHYSICAL REVIEW LETTERS 2005; 95:063601. [PMID: 16090952 DOI: 10.1103/physrevlett.95.063601] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Indexed: 05/03/2023]
Abstract
We report on the demonstration of light storage for times greater than a second in praseodymium doped Y2SiO5 using electromagnetically induced transparency. The long storage times were enabled by the long coherence times possible for the hyperfine transitions in this material. The use of a solid-state system also enabled operation with the probe and coupling beam counter-propagating, allowing easy separation of the two beams. The efficiency of the storage was low because of the low optical thickness of the sample; as is discussed, this deficiency should be easy to rectify.
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Affiliation(s)
- J J Longdell
- Laser Physics Centre, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200, Australia.
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305
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Rybin AV, Vadeiko IP, Bishop AR. Theory of slow-light solitons. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 72:026613. [PMID: 16196741 DOI: 10.1103/physreve.72.026613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2004] [Revised: 04/12/2005] [Indexed: 05/04/2023]
Abstract
In the framework of the nonlinear lambda model we investigate propagation of solitons in atomic vapors and Bose-Einstein condensates. We show how the complicated nonlinear interplay between fast solitons and slow-light solitons in the lambda-type media points to the possibility to create optical gates and, thus, to control the optical transparency of the lambda-type media. We provide an exact analytic description of decelerating, stopping and reaccelerating of slow-light solitons in atomic media in the nonadiabatic regime. Dynamical control over slow-light solitons is realized via a controlling field generated by an auxiliary laser. For a rather general time dependence of the field; we find the dynamics of the slow-light soliton inside the medium. We provide an analytical description for the nonlinear dependence of the velocity of the signal on the controlling field. If the background field is turned off at some moment of time, the signal stops. We find the location and shape of the spatially localized memory bit imprinted into the medium. We discuss physically interesting features of our solution, which are in a good agreement with recent experiments.
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Affiliation(s)
- A V Rybin
- Department of Physics, University of Jyväskylä, P.O. Box 35, FIN-40351 Jyväskylä, Finland.
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306
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Harada KI, Tanaka S, Kanbashi T, Mitsunaga M, Motomura K. Electromagnetically induced diffraction in sodium vapor. OPTICS LETTERS 2005; 30:2004-6. [PMID: 16092247 DOI: 10.1364/ol.30.002004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
By using a sodium atomic vapor we have observed a honeycomb-type multiple-diffraction pattern that was due to a grating induced optically by three noncollinear bichromatic excitation beams. In particular, when the two incident frequencies satisfy the two-photon resonance condition and the atomic density is high, the diffraction is enhanced by electromagnetically induced transparency, and strong Stokes and anti-Stokes components are generated in well-defined directions.
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Affiliation(s)
- Ken-ichi Harada
- Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami Kumamoto-shi, Kumamoto 860-8555, Japan
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307
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Benabid F, Light P, Couny F, Russell P. Electromagnetically-induced transparency grid in acetylene-filled hollow-core PCF. OPTICS EXPRESS 2005; 13:5694-5703. [PMID: 19498571 DOI: 10.1364/opex.13.005694] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report a set of experimental observations on electromagnetically induced transparency in acetylene filled hollow-core photonic crystal fiber, involving both Lambda-type and V-type interactions over several lines of the R-branch of the nu1 + nu3 ro-vibrational overtone band. Transparency as high as ~70% was achieved. A theoretical account of the sources of decoherence shows that collisions with the inner wall of the fiber core and laser frequency-jitter dominate the coherence decay.
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308
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Matsukevich DN, Chanelière T, Bhattacharya M, Lan SY, Jenkins SD, Kennedy TAB, Kuzmich A. Entanglement of a photon and a collective atomic excitation. PHYSICAL REVIEW LETTERS 2005; 95:040405. [PMID: 16090786 DOI: 10.1103/physrevlett.95.040405] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2005] [Indexed: 05/03/2023]
Abstract
We describe a new experimental approach to probabilistic atom-photon (signal) entanglement. Two qubit states are encoded as orthogonal collective spin excitations of an unpolarized atomic ensemble. After a programmable delay, the atomic excitation is converted into a photon (idler). Polarization states of both the signal and the idler are recorded and are found to be in violation of the Bell inequality. Atomic coherence times exceeding several microseconds are achieved by switching off all the trapping fields--including the quadrupole magnetic field of the magneto-optical trap--and zeroing out the residual ambient magnetic field.
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Affiliation(s)
- D N Matsukevich
- School of Physics, Georgia Institute of Technology, Atlanta, 30332-0430, USA
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309
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Petrosyan D. Towards deterministic optical quantum computation with coherently driven atomic ensembles. ACTA ACUST UNITED AC 2005. [DOI: 10.1088/1464-4266/7/7/003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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310
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Talukder AI, Haruta T, Tomita M. Measurement of net group and reshaping delays for optical pulses in dispersive media. PHYSICAL REVIEW LETTERS 2005; 94:223901. [PMID: 16090396 DOI: 10.1103/physrevlett.94.223901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Indexed: 05/03/2023]
Abstract
We experimentally demonstrate the direct measurement of net group and reshaping delays for arbitrary optical pulses in dispersive media, verifying the earlier prediction of Peatross et al. [Phys. Rev. Lett. 84, 2370 (2000)]. Incoherent pulse propagation in an absorptionless system is well described by net group delay; even the medium causes a great deal of deformation in the transmitted pulse. However, in the case of phase modulated chirping pulses in a resonant absorber, the so-called superluminal or subluminal propagation velocity is strongly influenced by the reshaping delay.
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Affiliation(s)
- Aminul I Talukder
- Department of Physics, Faculty of Science, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
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311
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Dutt MVG, Cheng J, Li B, Xu X, Li X, Berman PR, Steel DG, Bracker AS, Gammon D, Economou SE, Liu RB, Sham LJ. Stimulated and spontaneous optical generation of electron spin coherence in charged GaAs quantum dots. PHYSICAL REVIEW LETTERS 2005; 94:227403. [PMID: 16090438 DOI: 10.1103/physrevlett.94.227403] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2004] [Indexed: 05/03/2023]
Abstract
We report on the coherent optical excitation of electron spin polarization in the ground state of charged GaAs quantum dots via an intermediate charged exciton (trion) state. Coherent optical fields are used for the creation and detection of the Raman spin coherence between the spin ground states of the charged quantum dot. The measured spin decoherence time, which is likely limited by the nature of the spin ensemble, approaches 10 ns at zero field. We also show that the Raman spin coherence in the quantum beats is caused not only by the usual stimulated Raman interaction but also by simultaneous spontaneous radiative decay of either excited trion state to a coherent combination of the two spin states.
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Affiliation(s)
- M V Gurudev Dutt
- The H. M. Randall Laboratory of Physics, The University of Michigan, Ann Arbor, MI 48109, USA
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312
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Müstecaplioğlu OE, Oktel MO. Photonic band gap via quantum coherence in vortex lattices of Bose-Einstein condensates. PHYSICAL REVIEW LETTERS 2005; 94:220404. [PMID: 16090371 DOI: 10.1103/physrevlett.94.220404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Indexed: 05/03/2023]
Abstract
We investigate the optical response of an atomic Bose-Einstein condensate with a vortex lattice. We find that it is possible for the vortex lattice to act as a photonic crystal and create photonic band gaps, by enhancing the refractive index of the condensate via a quantum coherent scheme. If high enough index contrast between the vortex core and the atomic sample is achieved, a photonic band gap arises depending on the healing length and the lattice spacing. A wide range of experimentally accessible parameters are examined and band gaps in the visible region of the electromagnetic spectrum are found. We also show how directional band gaps can be used to directly measure the rotation frequency of the condensate.
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Affiliation(s)
- O E Müstecaplioğlu
- Department of Physics, Koç University, Rumelifeneri Yolu, 34450 Sariyer, Istanbul, Turkey
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313
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Hammerer K, Wolf MM, Polzik ES, Cirac JI. Quantum benchmark for storage and transmission of coherent states. PHYSICAL REVIEW LETTERS 2005; 94:150503. [PMID: 15904127 DOI: 10.1103/physrevlett.94.150503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Indexed: 05/02/2023]
Abstract
We consider the storage and transmission of a Gaussian distributed set of coherent states of continuous variable systems. We prove a limit on the average fidelity achievable when the states are transmitted or stored by a classical channel, i.e., a measure and repreparation scheme which sends or stores classical information only. The obtained bound is tight and serves as a benchmark which has to be surpassed by quantum channels in order to outperform any classical strategy. The success in experimental demonstrations of quantum memories as well as quantum teleportation has to be judged on this footing.
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Affiliation(s)
- K Hammerer
- Max-Planck-Institut für Quantenoptik, D-85748 Garching, Germany
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314
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Ghosh S, Sharping JE, Ouzounov DG, Gaeta AL. Resonant optical interactions with molecules confined in photonic band-gap fibers. PHYSICAL REVIEW LETTERS 2005; 94:093902. [PMID: 15783965 DOI: 10.1103/physrevlett.94.093902] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Indexed: 05/24/2023]
Abstract
We investigate resonant nonlinear optical interactions and demonstrate induced transparency in acetylene molecules in a hollow-core photonic-band-gap fiber at 1.5 mum. The induced spectral transmission window is used to demonstrate slow-light effects, and we show that the observed broadening of the spectral features is due to collisions of the molecules with the inner walls of the fiber core. Our results illustrate that such fibers can be used to facilitate strong coherent light-matter interactions even when the optical response of the individual molecules is weak.
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Affiliation(s)
- Saikat Ghosh
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
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315
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316
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André A, Bajcsy M, Zibrov AS, Lukin MD. Nonlinear optics with stationary pulses of light. PHYSICAL REVIEW LETTERS 2005; 94:063902. [PMID: 15783731 DOI: 10.1103/physrevlett.94.063902] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2004] [Indexed: 05/24/2023]
Abstract
We show that the recently demonstrated technique for generating stationary pulses of light [M. Bajcsy, A. S. Zibrov, and M. D. Lukin, Nature (London) 426, 638 (2003)] can be extended to localize optical pulses in all three spatial dimensions in a resonant atomic medium. This method can be used to dramatically enhance the nonlinear interaction between weak optical pulses. In particular, we show that an efficient Kerr-like interaction between two pulses can be implemented as a sequence of several purely linear optical processes. The resulting process may enable coherent interactions between single photon pulses.
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Affiliation(s)
- A André
- Physics Department, Harvard University, Cambridge, Massachusetts 02138, USA
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317
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Julsgaard B, Sherson J, Cirac JI, Fiurásek J, Polzik ES. Experimental demonstration of quantum memory for light. Nature 2004; 432:482-6. [PMID: 15565148 DOI: 10.1038/nature03064] [Citation(s) in RCA: 656] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2004] [Accepted: 09/28/2004] [Indexed: 11/08/2022]
Abstract
The information carrier of today's communications, a weak pulse of light, is an intrinsically quantum object. As a consequence, complete information about the pulse cannot be perfectly recorded in a classical memory, even in principle. In the field of quantum information, this has led to the long-standing challenge of how to achieve a high-fidelity transfer of an independently prepared quantum state of light onto an atomic quantum state. Here we propose and experimentally demonstrate a protocol for such a quantum memory based on atomic ensembles. Recording of an externally provided quantum state of light onto the atomic quantum memory is achieved with 70 per cent fidelity, significantly higher than the limit for classical recording. Quantum storage of light is achieved in three steps: first, interaction of the input pulse and an entangling field with spin-polarized caesium atoms; second, subsequent measurement of the transmitted light; and third, feedback onto the atoms using a radio-frequency magnetic pulse conditioned on the measurement result. The density of recorded states is 33 per cent higher than the best classical recording of light onto atoms, with a quantum memory lifetime of up to 4 milliseconds.
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Affiliation(s)
- Brian Julsgaard
- Niels Bohr Institute, Danish Quantum Optics Center-QUANTOP, Copenhagen University, Blegdamsvej 17, 2100 Copenhagen Ø, Denmark
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318
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Shumelyuk A, Shcherbin K, Odoulov S, Sturman B, Podivilov E, Buse K. Slowing down of light in photorefractive crystals with beam intensity coupling reduced to zero. PHYSICAL REVIEW LETTERS 2004; 93:243604. [PMID: 15697810 DOI: 10.1103/physrevlett.93.243604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2004] [Indexed: 05/24/2023]
Abstract
A considerable deceleration of light pulses in crystals with nearly compensated space-charge field proves that the strong dispersion of dynamic photorefractive gratings in the vicinity of Bragg resonance is of primary importance for light slowing down.
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Affiliation(s)
- A Shumelyuk
- Institute of Physics, National Academy of Sciences, 252650 Kiev, Ukraine
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319
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Yanik MF, Suh W, Wang Z, Fan S. Stopping light in a waveguide with an all-optical analog of electromagnetically induced transparency. PHYSICAL REVIEW LETTERS 2004; 93:233903. [PMID: 15601162 DOI: 10.1103/physrevlett.93.233903] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2004] [Indexed: 05/24/2023]
Abstract
We introduce a new all-optical mechanism that can compress the bandwidth of light pulses to absolute zero, and bring them to a complete stop. The mechanism can be realized in a system consisting of a waveguide side coupled to tunable resonators, which generates a photonic band structure that represents a classical analogue of the electromagnetically induced transparency. The same system can also achieve a time-reversal operation. We demonstrate the operation of such a system by finite-difference time-domain simulations of an implementation in photonic crystals.
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320
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Eisaman MD, Childress L, André A, Massou F, Zibrov AS, Lukin MD. Shaping quantum pulses of light via coherent atomic memory. PHYSICAL REVIEW LETTERS 2004; 93:233602. [PMID: 15601158 DOI: 10.1103/physrevlett.93.233602] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2004] [Indexed: 05/24/2023]
Abstract
We describe proof-of-principle experiments demonstrating a novel approach for generating pulses of light with controllable photon numbers, propagation direction, timing, and pulse shapes. The approach is based on preparation of an atomic ensemble in a state with a desired number of atomic spin excitations, which is later converted into a photon pulse. Spatiotemporal control over the pulses is obtained by exploiting long-lived coherent memory for photon states and Electromagnetically Induced Transparency in an optically dense atomic medium. Using photon counting experiments, we observe Electromagnetically Induced Transparency based generation and shaping of few-photon sub-Poissonian light pulses.
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Affiliation(s)
- M D Eisaman
- Physics Department, Harvard University, Cambridge, MA 02138, USA
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321
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Huss AF, Lammegger R, Neureiter C, Korsunsky EA, Windholz L. Phase correlation of laser waves with arbitrary frequency spacing. PHYSICAL REVIEW LETTERS 2004; 93:223601. [PMID: 15601089 DOI: 10.1103/physrevlett.93.223601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2004] [Indexed: 05/24/2023]
Abstract
The theoretically predicted correlation of laser phase fluctuations in Lambda-type interaction schemes is experimentally demonstrated. We show that the mechanism of correlation in a Lambda scheme is restricted to high-frequency noise components, whereas in a double-Lambda scheme, due to the laser phase locking in a closed-loop interaction, it extends to all noise frequencies. In this case the correlation is weakly sensitive to coherence losses. Thus the double-Lambda scheme can be used to correlate electromagnetic fields with carrier frequency differences beyond the GHz regime.
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Affiliation(s)
- A F Huss
- Institut für Experimentalphysik, Technische Universität Graz, Petersgasse 16, 8010 Graz, Austria
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322
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Chang H, Wu H, Xie C, Wang H. Controlled shift of optical bistability hysteresis curve and storage of optical signals in a four-level atomic system. PHYSICAL REVIEW LETTERS 2004; 93:213901. [PMID: 15601009 DOI: 10.1103/physrevlett.93.213901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2004] [Indexed: 05/24/2023]
Abstract
The dependence of the shift of an optical bistability hysteresis curve on the nonlinear phase shift induced by a controlling light is observed in a four-level atomic system of 87 Rb inside an optical ring cavity. In the process the intensity of the coupling beam keeps constant and the atomic system is operated at near conditions of coherent population trapping due to atomic coherence. The refractive and absorptive chi3 nonlinearities enhanced by atomic coherence provide the physical mechanism of the phenomena. Based on the effects, all-optical flip-flop and storage of optical pulse signals with a low peak power of several tens of microwatts are implemented.
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Affiliation(s)
- Hong Chang
- The State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, 030006, People's Republic of China
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323
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Dutton Z, Ruostekoski J. Transfer and storage of vortex states in light and matter waves. PHYSICAL REVIEW LETTERS 2004; 93:193602. [PMID: 15600834 DOI: 10.1103/physrevlett.93.193602] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2004] [Indexed: 05/24/2023]
Abstract
We theoretically explore the transfer of vortex states between atomic Bose-Einstein condensates and optical pulses using ultraslow and stopped light techniques. We find shining a coupling laser on a rotating two-component ground state condensate with a vortex lattice generates a probe laser field with optical vortices. We also find that optical vortex states can be robustly stored in the atomic superfluids for times, in Rb-87 condensates, limited only by the ground state coherence time.
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Affiliation(s)
- Zachary Dutton
- National Institute of Standards Technology, Electron and Optical Division, Gaithersburg, Maryland 20899-8410, USA
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324
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Buffa R, Cavalieri S, Tognetti MV. Temporal compression of short-wavelength laser pulses by coherent control in rare gases. OPTICS LETTERS 2004; 29:2432-2434. [PMID: 15532290 DOI: 10.1364/ol.29.002432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We present a theoretical study of temporal compression of a short-wavelength laser pulse predicted in a real, Doppler-broadened, atomic system. The compression is the result of the coherent control peculiarities of electromagnetically induced transparency-propagation dynamics. Numerical results are reported and discussed, showing a temporal compression of 2 orders of magnitude (from 10 ns to 100 ps) of a 106.7-nm laser pulse in argon atoms at room temperature.
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Affiliation(s)
- Roberto Buffa
- Dipartimento di Fisica dell'Università di Siena, and Istituto Nazionale per la Fisica della Materia, Siena, Italy
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325
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Zhang G, Bo F, Dong R, Xu J. Phase-coupling-induced ultraslow light propagation in solids at room temperature. PHYSICAL REVIEW LETTERS 2004; 93:133903. [PMID: 15524721 DOI: 10.1103/physrevlett.93.133903] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2004] [Indexed: 05/24/2023]
Abstract
We show that the group velocities of light pulses can be decelerated dramatically by the use of a dispersive phase-coupling effect through a wave mixing process. We have observed experimentally such a phase-coupling-induced ultraslow light propagation with a group velocity as low as 0.05 m/s in a photorefractive Bi12SiO20 crystal at room temperature. Moreover, the ultraslow light is amplified in the Bi12SiO20 crystal because of the unidirectional energy transfer from a coupling beam to the ultraslow light. This technique to produce ultraslow light propagation is valid for all nonlinear wave mixing processes with a dispersive phase-coupling effect.
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Affiliation(s)
- Guoquan Zhang
- Photonics Center, College of Physics Science, Nankai University, Tianjin 300071, China.
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326
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Kang H, Hernandez G, Zhu Y. Slow-light six-wave mixing at low light intensities. PHYSICAL REVIEW LETTERS 2004; 93:073601. [PMID: 15324236 DOI: 10.1103/physrevlett.93.073601] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2003] [Indexed: 05/24/2023]
Abstract
We report an experimental study of resonant six-wave mixing in coherently prepared Rb atoms. Electromagnetically induced transparency in a four-level atomic system suppresses the linear susceptibility and enhances the nonlinear susceptibilities, which leads to the resonantly enhanced, slow-photon six-wave mixing at low light intensities. The light emission in the six-wave mixing process can be viewed as resulting from diffraction of slow light off a resonant nonlinear grating induced in the four-level system by a standing-wave pump field.
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Affiliation(s)
- Hoonsoo Kang
- Department of Physics, Florida International University, Miami, Florida 33199, USA
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327
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Juzeliūnas G, Ohberg P. Slow light in degenerate fermi gases. PHYSICAL REVIEW LETTERS 2004; 93:033602. [PMID: 15323821 DOI: 10.1103/physrevlett.93.033602] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2004] [Indexed: 05/24/2023]
Abstract
We investigate the effect of slow light propagating in a degenerate atomic Fermi gas. In particular we use slow light with an orbital angular momentum. We present a microscopic theory for the interplay between light and matter and show how the slow light can provide an effective magnetic field acting on the electrically neutral fermions, a direct analogy of the free electron gas in an uniform magnetic field. As an example we illustrate how the corresponding de Haas-van Alphen effect can be seen in a gas of neutral atomic fermions.
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Affiliation(s)
- G Juzeliūnas
- Vilnius University Research Institute of Theoretical Physics and Astronomy, A. Gostauto 12, 2600 Vilnius, Lithuania
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328
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Murali KVRM, Son HB, Steffen M, Judeinstein P, Chuang IL. Test by NMR of the phase coherence of electromagnetically induced transparency. PHYSICAL REVIEW LETTERS 2004; 93:033601. [PMID: 15323820 DOI: 10.1103/physrevlett.93.033601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2003] [Indexed: 05/24/2023]
Abstract
Electromagnetically induced transparency is an effect observed in atomic systems, originating from quantum interference, in which electromagnetic transitions to and from a certain quantum state become suppressed. This dark state is also characterized by a quantum phase, relative to other states, which theoretically should stop evolving, but remain phase coherent, during transparency. We test this theoretical prediction using techniques developed for liquid-state nuclear magnetic resonance quantum computation, applied to a spin-7/2 nuclear spin system. A sequence of quantum operations is applied to create the dark state, and during transparency its phase evolution is measured relative to a reference state using Ramsey interferometry. Experimental measurements of the fringe visibility are in excellent agreement with theoretical expectations, taking into account measured decoherence rates.
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Affiliation(s)
- K V R M Murali
- Center for Bits and Atoms, MIT, Cambridge, Massachusetts 02139, USA
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329
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Barreiro S, Tabosa JWR, Torres JP, Deyanova Y, Torner L. Four-wave mixing of light beams with engineered orbital angular momentum in cold cesium atoms. OPTICS LETTERS 2004; 29:1515-1517. [PMID: 15259731 DOI: 10.1364/ol.29.001515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We report an experimental demonstration that shows that the spatial structure carried by engineered coherent superpositions of light beams with orbital angular momentum can be mapped into the nonlinear polarization induced in a cloud of cold cesium atoms. The structure of such polarization was revealed by nearly degenerate four-wave-mixing processes.
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Affiliation(s)
- S Barreiro
- Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil
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330
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Akamatsu D, Akiba K, Kozuma M. Electromagnetically induced transparency with squeezed vacuum. PHYSICAL REVIEW LETTERS 2004; 92:203602. [PMID: 15169353 DOI: 10.1103/physrevlett.92.203602] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2003] [Indexed: 05/24/2023]
Abstract
The squeezed vacuum resonant on the (87)Rb D1 line (probe light) was injected into an optically dense rubidium gas cell with a coherent light (control light). The output probe light maintained its quadrature squeezing within the transparency window caused by the electromagnetically induced transparency (EIT). The results reported here are the first realization of EIT in the full quantum regime.
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Affiliation(s)
- Daisuke Akamatsu
- Department of Physics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8550, Japan
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331
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Agarwal GS, Dey TN. Sub- and superluminal propagation of intense pulses in media with saturated and reverse absorption. PHYSICAL REVIEW LETTERS 2004; 92:203901. [PMID: 15169354 DOI: 10.1103/physrevlett.92.203901] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2003] [Indexed: 05/24/2023]
Abstract
We develop models for the propagation of intense pulses in solid state media which can have either saturated absorption or reverse absorption. We model subluminal propagation in ruby and superluminal propagation in alexandrite as three and four level systems, respectively, coupled to Maxwell's equations. We present results well beyond the traditional pump-probe approach and explain the experiments of Bigelow et al. [Phys. Rev. Lett. 90, 113903 (2003)]Science 301, 200 (2003)]] on solid state materials.
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Affiliation(s)
- G S Agarwal
- Physical Research Laboratory, Navrangpura, Ahmedabad-380 009, India
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332
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Yanik MF, Fan S. Stopping light all optically. PHYSICAL REVIEW LETTERS 2004; 92:083901. [PMID: 14995773 DOI: 10.1103/physrevlett.92.083901] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2003] [Indexed: 05/24/2023]
Abstract
We show that light pulses can be stopped and stored coherently, with an all-optical adiabatic and reversible pulse bandwidth compression process. Such a process overcomes the fundamental bandwidth-delay constraint in optics and can generate arbitrarily small group velocities for any light pulse with a given bandwidth, without any coherent or resonant light-matter interactions. We exhibit this process in optical resonators, where the bandwidth compression is accomplished only by small refractive-index modulations performed at moderate speeds.
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Affiliation(s)
- Mehmet Fatih Yanik
- Ginzton Laboratory, Stanford University, Stanford, California 94305, USA
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333
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Zhang G, Dong R, Bo F, Xu J. Slowdown of group velocity of light by means of phase coupling in photorefractive two-wave mixing. APPLIED OPTICS 2004; 43:1167-1173. [PMID: 15008499 DOI: 10.1364/ao.43.001167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We show theoretically that the group velocity of light can be slowed down by means of phase coupling in the photorefractive two-wave mixing process. It is shown that the group velocity of light propagating in a photorefractive material could be significantly reduced because of a steep variation of the phase-coupling coefficient with respect to the angular frequency difference between two coupling beams in a two-wave mixing process. The results for the case of a photorefractive Bi12SiO20 crystal are presented and discussed in detail.
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Affiliation(s)
- Guoquan Zhang
- Photonics Research Center, College of Physical Science, Nankai University, Tianjin, 300071, China.
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334
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335
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Bajcsy M, Zibrov AS, Lukin MD. Stationary pulses of light in an atomic medium. Nature 2003; 426:638-41. [PMID: 14668857 DOI: 10.1038/nature02176] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2003] [Accepted: 11/04/2003] [Indexed: 11/09/2022]
Abstract
Physical processes that could facilitate coherent control of light propagation are under active exploration. In addition to their fundamental interest, these efforts are stimulated by practical possibilities, such as the development of a quantum memory for photonic states. Controlled localization and storage of photonic pulses may also allow novel approaches to manipulating of light via enhanced nonlinear optical processes. Recently, electromagnetically induced transparency was used to reduce the group velocity of propagating light pulses and to reversibly map propagating light pulses into stationary spin excitations in atomic media. Here we describe and experimentally demonstrate a technique in which light propagating in a medium of Rb atoms is converted into an excitation with localized, stationary electromagnetic energy, which can be held and released after a controllable interval. Our method creates pulses of light with stationary envelopes bound to an atomic spin coherence, offering new possibilities for photon state manipulation and nonlinear optical processes at low light levels.
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Affiliation(s)
- M Bajcsy
- Physics Department, Harvard University, Cambridge, Massachusetts 02138, USA
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336
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Labeyrie G, Vaujour E, Müller CA, Delande D, Miniatura C, Wilkowski D, Kaiser R. Slow diffusion of light in a cold atomic cloud. PHYSICAL REVIEW LETTERS 2003; 91:223904. [PMID: 14683240 DOI: 10.1103/physrevlett.91.223904] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2003] [Indexed: 05/24/2023]
Abstract
We study the diffusive propagation of multiply scattered light in an optically thick cloud of cold rubidium atoms illuminated by a quasiresonant laser beam. In the vicinity of a sharp atomic resonance, the energy transport velocity of the scattered light is almost 5 orders of magnitude smaller than the vacuum speed of light, reducing strongly the diffusion constant. We verify the theoretical prediction of a frequency-independent transport time around the resonance. We also observe the effect of the residual velocity of the atoms at long times.
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Affiliation(s)
- G Labeyrie
- Laboratoire Ondes et Désordre, FRE 2302 CNRS, 1361 route des Lucioles, F-06560 Valbonne, France.
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337
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Gingrich RM, Kok P, Lee H, Vatan F, Dowling JP. All linear optical quantum memory based on quantum error correction. PHYSICAL REVIEW LETTERS 2003; 91:217901. [PMID: 14683335 DOI: 10.1103/physrevlett.91.217901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2003] [Indexed: 05/24/2023]
Abstract
When photons are sent through a fiber as part of a quantum communication protocol, the error that is most difficult to correct is photon loss. Here we propose and analyze a two-to-four qubit encoding scheme, which can recover the loss of one qubit in the transmission. This device acts as a repeater, when it is placed in series to cover a distance larger than the attenuation length of the fiber, and it acts as an optical quantum memory, when it is inserted in a fiber loop. We call this dual-purpose device a "quantum transponder."
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Affiliation(s)
- Robert M Gingrich
- Quantum Computing Technologies Group, Section 367, California Institute of Technology, MS 126-347, 4800 Oak Grove Drive, California 91109-8099, USA
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338
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Phillips MC, Wang H, Rumyantsev I, Kwong NH, Takayama R, Binder R. Electromagnetically induced transparency in semiconductors via biexciton coherence. PHYSICAL REVIEW LETTERS 2003; 91:183602. [PMID: 14611283 DOI: 10.1103/physrevlett.91.183602] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2003] [Indexed: 05/24/2023]
Abstract
We report an experimental demonstration and theoretical analysis of electromagnetically induced transparency in a GaAs quantum well, in which the absorption of an exciton resonance is reduced by more than twentyfold. The destructive quantum interference in this scheme is set up by a control pulse that couples to a resonance of biexcitons. These studies illustrate that many-particle interactions, which are inherent in semiconductors and are often detrimental to quantum coherences, can also be harnessed to manipulate these coherences.
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Affiliation(s)
- Mark C Phillips
- Department of Physics, University of Oregon, Eugene, OR 97403, USA
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339
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Sun CP, Li Y, Liu XF. Quasi-spin-wave quantum memories with a dynamical symmetry. PHYSICAL REVIEW LETTERS 2003; 91:147903. [PMID: 14611556 DOI: 10.1103/physrevlett.91.147903] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2002] [Indexed: 05/24/2023]
Abstract
For the two-mode exciton system formed by the quasi-spin-wave collective excitation of many Lambda atoms fixed at the lattice sites of a crystal, we discover a dynamical symmetry depicted by the semidirect product algebra SU2( multiply sign in circle) h(2) in the large N limit with low excitations. With the help of the spectral generating algebra method, we obtain a larger class of exact zero-eigenvalue states adiabatically interpolating between the initial state of photon-type and the final state of quasi-spin-wave exciton-type. The conditions for the adiabatic passage of dark states are shown to be valid, even with the presence of the level degeneracy. These theoretical results can lead to the proposal of a new protocol for implementing quantum memory robust against quantum decoherence.
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Affiliation(s)
- C P Sun
- Institute of Theoretical Physics, The Chinese Academy of Science, Beijing, 100080, China.
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340
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Julsgaard B, Sherson J, Sørensen JL, Polzik ES. Characterizing the spin state of an atomic ensemble using the magneto-optical resonance method. ACTA ACUST UNITED AC 2003. [DOI: 10.1088/1464-4266/6/1/002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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341
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Podivilov E, Sturman B, Shumelyuk A, Odoulov S. Light pulse slowing down up to 0.025 cm/s by photorefractive two-wave coupling. PHYSICAL REVIEW LETTERS 2003; 91:083902. [PMID: 14525239 DOI: 10.1103/physrevlett.91.083902] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2003] [Indexed: 05/24/2023]
Abstract
It is shown experimentally and theoretically that photorefractive wave coupling can be used for dramatic (< or approximately 0.025 cm/s) deceleration of light pulses whose width is larger than (or comparable with) the nonlinear response time. This classical nonlinear scheme exhibits similarities with the technique based on the quantum effect of electromagnetically induced transparency. The main distinctive feature of our scheme is amplification of the delayed output pulse. Advantages of the novel technique and its prospects for manipulation with light photons are discussed.
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Affiliation(s)
- E Podivilov
- Institute of Automation and Electrometry, 630090 Novosibirsk, Russia
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342
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Moiseev SA, Tarasov VF, Ham BS. Quantum memory photon echo-like techniques in solids. ACTA ACUST UNITED AC 2003. [DOI: 10.1088/1464-4266/5/4/356] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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343
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van der Wal CH, Eisaman MD, André A, Walsworth RL, Phillips DF, Zibrov AS, Lukin MD. Atomic memory for correlated photon states. Science 2003; 301:196-200. [PMID: 12764202 DOI: 10.1126/science.1085946] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We experimentally demonstrate emission of two quantum-mechanically correlated light pulses with a time delay that is coherently controlled via temporal storage of photonic states in an ensemble of rubidium atoms. The experiment is based on Raman scattering, which produces correlated pairs of spin-flipped atoms and photons, followed by coherent conversion of the atomic states into a different photon beam after a controllable delay. This resonant nonlinear optical process is a promising technique for potential applications in quantum communication.
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Affiliation(s)
- C H van der Wal
- Department of Physics, Harvard University, Cambridge, MA 02138, USA
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344
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Bigelow MS, Lepeshkin NN, Boyd RW. Superluminal and slow light propagation in a room-temperature solid. Science 2003; 301:200-2. [PMID: 12855803 DOI: 10.1126/science.1084429] [Citation(s) in RCA: 153] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We have observed both superluminal and ultraslow light propagation in an alexandrite crystal at room temperature. Group velocities as slow as 91 meters per second to as fast as -800 meters per second were measured and attributed to the influence of coherent population oscillations involving chromium ions in either mirror or inversion sites within the crystal lattice. Namely, ions in mirror sites are inversely saturable and cause superluminal light propagation, whereas ions in inversion sites experience conventional saturable absorption and produce slow light. This technique for producing large group indices is considerably easier than the existing methods to implement and is therefore suitable for diverse applications.
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Affiliation(s)
- Matthew S Bigelow
- Institute of Optics, University of Rochester, Rochester, NY 14627, USA.
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345
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Reed EJ, Soljacić M, Joannopoulos JD. Color of shock waves in photonic crystals. PHYSICAL REVIEW LETTERS 2003; 90:203904. [PMID: 12785897 DOI: 10.1103/physrevlett.90.203904] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2002] [Indexed: 05/24/2023]
Abstract
Unexpected and stunning new physical phenomena result when light interacts with a shock wave or shocklike dielectric modulation propagating through a photonic crystal. These new phenomena include the capture of light at the shock wave front and reemission at a tunable pulse rate and carrier frequency across the band gap, and bandwidth narrowing as opposed to the ubiquitous bandwidth broadening. To our knowledge, these effects do not occur in any other physical system and are all realizable under experimentally accessible conditions. Furthermore, their generality make them amenable to observation in a variety of time-dependent photonic crystal systems, which has significant technological implications.
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Affiliation(s)
- Evan J Reed
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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346
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Barreiro S, Tabosa JWR. Generation of light carrying orbital angular momentum via induced coherence grating in cold atoms. PHYSICAL REVIEW LETTERS 2003; 90:133001. [PMID: 12689281 DOI: 10.1103/physrevlett.90.133001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2002] [Indexed: 05/24/2023]
Abstract
We report on the generation of light carrying orbital angular momentum through Bragg diffraction into an electromagnetically induced coherence grating in a degenerate two-level system of cold cesium atoms. The induced Zeeman coherence grating is shown to contain the spatial phase structure of the incident beams. The exchange of phase information between a light beam with orbital angular momentum and a long-lived atomic coherence opens up the way to process quantum information encoded in a multidimensional state space.
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Affiliation(s)
- S Barreiro
- Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife-PE, Brazil
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347
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Bigelow MS, Lepeshkin NN, Boyd RW. Observation of ultraslow light propagation in a ruby crystal at room temperature. PHYSICAL REVIEW LETTERS 2003; 90:113903. [PMID: 12688928 DOI: 10.1103/physrevlett.90.113903] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2002] [Indexed: 05/24/2023]
Abstract
We have observed slow light propagation with a group velocity as low as 57.5+/-0.5 m/s at room temperature in a ruby crystal. A quantum coherence effect, coherent population oscillations, produces a very narrow spectral "hole" in the homogeneously broadened absorption profile of ruby. The resulting rapid spectral variation of the refractive index leads to a large value of the group index. We observe slow light propagation both for Gaussian-shaped light pulses and for amplitude modulated optical beams in a system that is much simpler than those previously used for generating slow light.
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Affiliation(s)
- Matthew S Bigelow
- The Institute of Optics, University of Rochester, Rochester, New York 14627, USA
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348
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Abstract
Multiphoton excitation in a two-level system is exceedingly weak because of small multiphoton coupling strengths, large ac Stark shifts, and ionization. I will discuss a three-level system in which the ac Stark shift is greatly reduced and the multiphoton coupling strength is greatly enhanced over a two-level system, to such an extent that multiphoton pi pulses can be produced. I will also present two-electron calculations in a model potential, including ionization that shows a 12-photon pi pulse driven with 800-nm photons. This three-level configuration may provide the basis for an amplifying medium in the vacuum ultraviolet, as well as multiphoton adiabatic passage and innershell ionization.
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Affiliation(s)
- George N Gibson
- Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA
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349
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Thanopulos I, Shapiro M. Slowing down of light by laser induced barrier hopping. J Chem Phys 2002. [DOI: 10.1063/1.1506909] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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350
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James DFV, Kwiat PG. Atomic-vapor-based high efficiency optical detectors with photon number resolution. PHYSICAL REVIEW LETTERS 2002; 89:183601. [PMID: 12398600 DOI: 10.1103/physrevlett.89.183601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2002] [Indexed: 05/24/2023]
Abstract
The ability to detect very weak optical fields with high efficiency (>99%) and to distinguish the number of photons in a given time interval is a very challenging technical problem with enormous potential payoffs in quantum communications and information processing. We propose to employ an atomic vapor as the active medium, prepared in a specific quantum state using laser radiation. The absorption of a photon will be aided by a dressing laser, and the presence or absence of an excited atom will be detected using the "cycling transition" approach perfected for ion traps. By incorporating an appropriate up-conversion scheme, our method can be applied to a wide variety of optical wavelengths.
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Affiliation(s)
- Daniel F V James
- Theoretical Division T-4, University of California, Los Alamos National Laboratory, MS B-283, P.O. Box 1663, Los Alamos, New Mexico 87545, USA.
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