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Yu Z, Wu Z, Li X, Feng X, Huang W, Zhang K, Yuan CH, Zhang W, Chen LQ. Interferometry-Integrated Noise-Immune Quantum Memory. Phys Rev Lett 2023; 131:150804. [PMID: 37897768 DOI: 10.1103/physrevlett.131.150804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 09/18/2023] [Indexed: 10/30/2023]
Abstract
A quantum memory with the performances of low noise, high efficiency, and high bandwidth is of crucial importance for developing practical quantum information technologies. However, the excess noises generated during the highly efficient processing of quantum information inevitably destroy quantum state. Here, we present a quantum memory with built-in excess-noise eraser by integrating a photon-correlated quantum interferometry in quantum memory, where the memory efficiency can be enhanced and the excess noises can be suppressed to the vacuum level via destructive interference. This quantum memory is demonstrated in a rubidium vapor cell with a 10-ns-long photonics signal. We observe ∼80% noise suppression, the write-in efficiency enhancement from 87% to 96.2% without and with interferometry, and the corresponding memory efficiency excluding the noises from 70% to 77%. The fidelity is 93.7% at the single-photon level, significantly exceeding the no-cloning limit. Such interferometry-integrated quantum memory, the first expansion of quantum interference techniques to quantum information processing, simultaneously enables low noise, high bandwidth, high efficiency, and easy operation.
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Affiliation(s)
- Zhifei Yu
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Zeliang Wu
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Xuejie Li
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Xiaotian Feng
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Wenfeng Huang
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Keye Zhang
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Chun-Hua Yuan
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
| | - Weiping Zhang
- School of Physics and Astronomy, and Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
- Shanghai Branch, Hefei National Laboratory, Shanghai 201315, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
- Shanghai Research center for Quantum Science, Shanghai 201315, China
| | - L Q Chen
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
- Shanghai Branch, Hefei National Laboratory, Shanghai 201315, China
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2
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Businger M, Nicolas L, Mejia TS, Ferrier A, Goldner P, Afzelius M. Non-classical correlations over 1250 modes between telecom photons and 979-nm photons stored in 171Yb 3+:Y 2SiO 5. Nat Commun 2022; 13:6438. [PMID: 36307421 DOI: 10.1038/s41467-022-33929-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 10/07/2022] [Indexed: 11/15/2022] Open
Abstract
Quantum repeaters based on heralded entanglement require quantum nodes that are able to generate multimode quantum correlations between memories and telecommunication photons. The communication rate scales linearly with the number of modes, yet highly multimode quantum storage remains challenging. In this work, we demonstrate an atomic frequency comb quantum memory with a time-domain mode capacity of 1250 modes and a bandwidth of 100 MHz. The memory is based on a Y2SiO5 crystal doped with 171Yb3+ ions, with a memory wavelength of 979 nm. The memory is interfaced with a source of non-degenerate photon pairs at 979 and 1550 nm, bandwidth-matched to the quantum memory. We obtain strong non-classical second-order cross correlations over all modes, for storage times of up to 25 μs. The telecommunication photons propagated through 5 km of fiber before the release of the memory photons, a key capability for quantum repeaters based on heralded entanglement and feed-forward operations. Building on this experiment should allow distribution of entanglement between remote quantum nodes, with enhanced rates owing to the high multimode capacity. Multimode operation would greatly improve the performances of quantum repeaters. Here, the authors demonstrate a fixed-delay atomic frequency comb quantum memory, based on a Y2SiO5 crystal doped with Ytterbium ions, with a time-domain mode capacity of 1250 modes and a bandwidth of 100 MHz.
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Kaur T, Kaur M, Arvind, Arora B. Generating Sustained Coherence in a Quantum Memory for Retrieval at Times of Quantum Revival. Atoms 2022; 10:81. [DOI: 10.3390/atoms10030081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We study the time degradation of quantum information stored in a quantum memory device under a dissipative environment in a parameter range which is experimentally relevant. The quantum memory under consideration is comprised of an optomechanical system with additional Kerr nonlinearity in the optical mode and an anharmonic mechanical oscillator with quadratic nonlinearity. Time degradation is monitored, both in terms of loss of coherence, which is analyzed with the help of Wigner functions, as well as in terms of loss of amplitude of the original state, studied as a function of time. While our time trajectories explore the degree to which the stored information degrades depending upon the variation in values of various parameters involved, we suggest a set of parameters for which the original information can be retrieved without degradation. We identify a very interesting situation where the role played by the nonlinearity is insignificant, and the system behaves as if the information is stored in a linear medium. For this case, the information retrieval is independent of the coherence revival time and can be retrieved at any instant during the time evolution.
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Main D, Hird TM, Gao S, Walmsley IA, Ledingham PM. Room temperature atomic frequency comb storage for light. Opt Lett 2021; 46:2960-2963. [PMID: 34129584 DOI: 10.1364/ol.426753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/13/2021] [Indexed: 06/12/2023]
Abstract
We demonstrate coherent storage and retrieval of pulsed light using the atomic frequency comb protocol in a room temperature alkali vapor. We utilize velocity-selective optical pumping to prepare multiple velocity classes in the F=4 hyperfine ground state of cesium. The frequency spacing of the classes is chosen to coincide with the F'=4-F'=5 hyperfine splitting of the 62P3/2 excited state, resulting in a broadband periodic absorbing structure consisting of two usually Doppler-broadened optical transitions. Weak coherent states of duration 2ns are mapped into this atomic frequency comb with pre-programmed recall times of 8ns and 12ns, with multi-temporal mode storage and recall demonstrated. Utilizing two transitions in the comb leads to an additional interference effect upon rephasing that enhances the recall efficiency.
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Ma L, Slattery O, Tang X. Optical Quantum Memory and its Applications in Quantum Communication Systems. J Res Natl Inst Stand Technol 2020; 125:125002. [PMID: 35646477 PMCID: PMC9119665 DOI: 10.6028/jres.125.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 12/09/2019] [Indexed: 06/15/2023]
Abstract
Optical quantum memory is a device that can store the quantum state of photons and retrieve it on demand and with high fidelity. It is emerging as an essential device to enhance security, speed, scalability, and performance of many quantum systems used in communications, computing, metrology, and more. In this paper, we will specifically consider the impact of optical quantum memory on quantum communications systems. Following a general overview of the theoretical and experimental research progress in optical quantum memory, we will outline its role in quantum communications, including as a photon source, photon interference, quantum key distribution (QKD), quantum teleportation, quantum repeater, and quantum networks.
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Affiliation(s)
- Lijun Ma
- National Institute of Standards and Technology,Gaithersburg, MD 20899
USA
| | - Oliver Slattery
- National Institute of Standards and Technology,Gaithersburg, MD 20899
USA
| | - Xiao Tang
- National Institute of Standards and Technology,Gaithersburg, MD 20899
USA
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6
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Cox KC, Meyer DH, Castillo ZA, Fatemi FK, Kunz PD. Spin-Wave Multiplexed Atom-Cavity Electrodynamics. Phys Rev Lett 2019; 123:263601. [PMID: 31951441 DOI: 10.1103/physrevlett.123.263601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Indexed: 06/10/2023]
Abstract
We introduce multiplexed atom-cavity quantum electrodynamics with an atomic ensemble coupled to a single optical cavity mode. Multiple Raman dressing beams establish cavity-coupled spin-wave excitations with distinctive spatial profiles. Experimentally, we demonstrate the concept by observing spin-wave vacuum Rabi splittings, selective superradiance, and interference in the cavity-mediated interactions of two spin waves. We highlight that the current experimental configuration allows rapid, interchangeable cavity coupling to 4 profiles with an overlap parameter of less than 10%, enough to demonstrate, for example, a quantum repeater network simulation in the cavity. With further improvements to the optical multiplexing setup, we infer the ability to access more than 10^{3} independent spin-wave profiles.
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Affiliation(s)
- Kevin C Cox
- U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783, USA
| | - David H Meyer
- U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783, USA
| | - Zachary A Castillo
- U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783, USA
- Department of Physics, University of Maryland, College Park, Maryland 20742, USA
| | - Fredrik K Fatemi
- U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783, USA
| | - Paul D Kunz
- U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783, USA
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Fan HQ, Kagalwala KH, Polyakov SV, Migdall AL, Goldschmidt EA. Electromagnetically induced transparency in inhomogeneously broadened solid media. Phys Rev A (Coll Park) 2019; 99:053821. [PMID: 38510460 PMCID: PMC10953566 DOI: 10.1103/physreva.99.053821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
We study, theoretically and experimentally, electromagnetically induced transparency (EIT) in two different solid-state systems. Unlike many implementations in homogeneously broadened media, these systems exhibit inhomogeneous broadening of their optical and spin transitions typical of solid-state materials. We observe EIT lineshapes typical of atomic gases, including a crossover into the regime of Autler-Townes splitting, but with the substitution of the inhomogeneous widths for the homogeneous values. We obtain quantitative agreement between experiment and theory for the width of the transparency feature over a range of optical powers and inhomogeneous linewidths. We discuss regimes over which analytical and numerical treatments capture the behavior. As solid-state systems become increasingly important for scalable and integratable quantum optical and photonic devices, it is vital to understand the effects of the inhomogeneous broadening that is ubiquitous in these systems. The treatment presented here can be applied to a variety of systems, as exemplified by the common scaling of experimental results from two different systems.
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Affiliation(s)
- H. Q. Fan
- United States Army Research Laboratory, Adelphi, Maryland 20783, USA
- Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA
| | - K. H. Kagalwala
- Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA
| | - S. V. Polyakov
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - A. L. Migdall
- Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - E. A. Goldschmidt
- United States Army Research Laboratory, Adelphi, Maryland 20783, USA
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8
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Vernaz-Gris P, Tranter AD, Everett JL, Leung AC, Paul KV, Campbell GT, Lam PK, Buchler BC. High-performance Raman memory with spatio-temporal reversal. Opt Express 2018; 26:12424-12431. [PMID: 29801280 DOI: 10.1364/oe.26.012424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/19/2018] [Indexed: 06/08/2023]
Abstract
A number of techniques exist to use an ensemble of atoms as a quantum memory for light. Many of these propose to use backward retrieval as a way to improve the storage and recall efficiency. We report on a demonstration of an off-resonant Raman memory that uses backward retrieval to achieve an efficiency of 65 ± 6% at a storage time of one pulse duration. The memory has a characteristic decay time of 60 μs, corresponding to a delay-bandwidth product of 160.
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9
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Abstract
Electromagnetically induced transparency (EIT) is a promising approach to implement quantum memory in quantum communication and quantum computing applications. In this paper, following a brief overview of the main approaches to quantum memory, we provide details of the physical principle and theory of quantum memory based specifically on EIT. We discuss the key technologies for implementing quantum memory based on EIT and review important milestones, from the first experimental demonstration to current applications in quantum information systems.
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Affiliation(s)
- Lijun Ma
- Information Technology Laboratory, National Institute of Standards and Technology, 100 Bureau Dr, Gaithersburg, MD 20899, United States of America
| | - Oliver Slattery
- Information Technology Laboratory, National Institute of Standards and Technology, 100 Bureau Dr, Gaithersburg, MD 20899, United States of America
| | - Xiao Tang
- Information Technology Laboratory, National Institute of Standards and Technology, 100 Bureau Dr, Gaithersburg, MD 20899, United States of America
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10
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Bai Z, Xu D, Huang G. Storage and retrieval of electromagnetic waves with orbital angular momentum via plasmon-induced transparency. Opt Express 2017; 25:785-798. [PMID: 28157967 DOI: 10.1364/oe.25.000785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We propose a scheme to realize the storage and retrieval of high-dimensional electromagnetic waves with orbital angular momentum (OAM) via plasmon-induced transparency (PIT) in a metamaterial, which consists of an array of meta-atoms constructed by a metallic structure loaded with two varactors. We show that due to PIT effect the system allows the existence of shape-preserving dark-mode plasmonic polaritons, which are mixture of electromagnetic-wave modes and dark oscillatory modes of the meta-atoms and may carry various OAMs. We demonstrate that the slowdown, storage and retrieval of multi-mode electromagnetic waves with OAMs can be achieved through the active manipulation of a control field. Our work raises the possibility for realizing PIT-based spatial multi-mode memory of electromagnetic waves and is promising for practical application of information processing with large capacity by using room-temperature metamaterials.
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11
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Ahlefeldt RL, Hush MR, Sellars MJ. Ultranarrow Optical Inhomogeneous Linewidth in a Stoichiometric Rare-Earth Crystal. Phys Rev Lett 2016; 117:250504. [PMID: 28036212 DOI: 10.1103/physrevlett.117.250504] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 06/06/2023]
Abstract
We obtain a low optical inhomogeneous linewidth of 25 MHz in the stoichiometric rare-earth crystal EuCl_{3}·6H_{2}O by isotopically purifying the crystal in ^{35}Cl. With this linewidth, an important limit for stoichiometric rare-earth crystals is surpassed: the hyperfine structure of ^{153}Eu is spectrally resolved, allowing the whole population of ^{153}Eu^{3+} ions to be prepared in the same hyperfine state using hole-burning techniques. This material also has a very high optical density, and can have long coherence times when deuterated. This combination of properties offers new prospects for quantum information applications. We consider two of these: quantum memories and quantum many-body studies. We detail the improvements in the performance of current memory protocols possible in these high optical depth crystals, and describe how certain memory protocols, such as off-resonant Raman memories, can be implemented for the first time in a solid-state system. We explain how the strong excitation-induced interactions observed in this material resemble those seen in Rydberg systems, and describe how these interactions can lead to quantum many-body states that could be observed using standard optical spectroscopy techniques.
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Affiliation(s)
- R L Ahlefeldt
- Department of Physics, Montana State University, Bozeman, Montana 59717, USA
- Laser Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
| | - M R Hush
- School of Engineering and Information Technology, University of New South Wales at the Australian Defence Force Academy, Canberra 2600, Australia
| | - M J Sellars
- Centre for Quantum Computation and Communication Technology, Research School of Physics and Engineering, The Australian National University, Canberra 0200, Australia
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12
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Tiranov A, Strassmann PC, Lavoie J, Brunner N, Huber M, Verma VB, Nam SW, Mirin RP, Lita AE, Marsili F, Afzelius M, Bussières F, Gisin N. Temporal Multimode Storage of Entangled Photon Pairs. Phys Rev Lett 2016; 117:240506. [PMID: 28009181 DOI: 10.1103/physrevlett.117.240506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Indexed: 06/06/2023]
Abstract
Multiplexed quantum memories capable of storing and processing entangled photons are essential for the development of quantum networks. In this context, we demonstrate and certify the simultaneous storage and retrieval of two entangled photons inside a solid-state quantum memory and measure a temporal multimode capacity of ten modes. This is achieved by producing two polarization-entangled pairs from parametric down-conversion and mapping one photon of each pair onto a rare-earth-ion-doped (REID) crystal using the atomic frequency comb (AFC) protocol. We develop a concept of indirect entanglement witnesses, which can be used as Schmidt number witnesses, and we use it to experimentally certify the presence of more than one entangled pair retrieved from the quantum memory. Our work puts forward REID-AFC as a platform compatible with temporal multiplexing of several entangled photon pairs along with a new entanglement certification method, useful for the characterization of multiplexed quantum memories.
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Affiliation(s)
- Alexey Tiranov
- Groupe de Physique Appliquée, Université de Genève, CH-1211 Genève, Switzerland
| | - Peter C Strassmann
- Groupe de Physique Appliquée, Université de Genève, CH-1211 Genève, Switzerland
| | - Jonathan Lavoie
- Groupe de Physique Appliquée, Université de Genève, CH-1211 Genève, Switzerland
| | - Nicolas Brunner
- Département Physique Théorique, Université de Genève, CH-1211 Genève, Switzerland
| | - Marcus Huber
- Groupe de Physique Appliquée, Université de Genève, CH-1211 Genève, Switzerland
- Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna, Austria
| | - Varun B Verma
- National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
| | - Sae Woo Nam
- National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
| | - Richard P Mirin
- National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
| | - Adriana E Lita
- National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
| | - Francesco Marsili
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, California 91109, USA
| | - Mikael Afzelius
- Groupe de Physique Appliquée, Université de Genève, CH-1211 Genève, Switzerland
| | - Félix Bussières
- Groupe de Physique Appliquée, Université de Genève, CH-1211 Genève, Switzerland
| | - Nicolas Gisin
- Groupe de Physique Appliquée, Université de Genève, CH-1211 Genève, Switzerland
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13
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Klimek A, Jachura M, Wasilewski W, Banaszek K. Quantum memory receiver for superadditive communication using binary coherent states. J Mod Opt 2016; 63:2074-2080. [PMID: 27695200 PMCID: PMC5020343 DOI: 10.1080/09500340.2016.1173731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 03/29/2016] [Indexed: 06/06/2023]
Abstract
We propose a simple architecture based on multimode quantum memories for collective readout of classical information keyed using a pair coherent states, exemplified by the well-known binary phase shift keying format. Such a configuration enables demonstration of the superadditivity effect in classical communication over quantum channels, where the transmission rate becomes enhanced through joint detection applied to multiple channel uses. The proposed scheme relies on the recently introduced idea to prepare Hadamard sequences of input symbols that are mapped by a linear optical transformation onto the pulse position modulation format [Guha, S. Phys. Rev. Lett.2011, 106, 240502]. We analyze two versions of readout based on direct detection and an optional Dolinar receiver which implements the minimum-error measurement for individual detection of a binary coherent state alphabet.
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Affiliation(s)
| | - Michał Jachura
- Wydział Fizyki, Uniwersytet Warszawski, Warszawa, Poland
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14
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Dąbrowski M, Chrapkiewicz R, Wasilewski W. Magnetically tuned, robust and efficient filtering system for spatially multimode quantum memory in warm atomic vapors. J Mod Opt 2016; 63:2029-2038. [PMID: 27695199 PMCID: PMC5020350 DOI: 10.1080/09500340.2015.1106016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/01/2015] [Indexed: 05/29/2023]
Abstract
Warm atomic vapor quantum memories are simple and robust, yet suffer from a number of parasitic processes which produce excess noise. For operating in a single-photon regime precise filtering of the output light is essential. Here, we report a combination of magnetically tuned absorption and Faraday filters, both light-direction insensitive, which stop the driving lasers and attenuate spurious fluorescence and four-wave mixing while transmitting narrowband Stokes and anti-Stokes photons generated in write-in and readout processes. We characterize both filters with respect to adjustable working parameters. We demonstrate a significant increase in the signal-to-noise ratio upon applying the filters seen qualitatively in measurements of correlation between the Raman scattered photons.
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Affiliation(s)
- M. Dąbrowski
- Institute of Experimental Physics, University of Warsaw, Warsaw, Poland
| | - R. Chrapkiewicz
- Institute of Experimental Physics, University of Warsaw, Warsaw, Poland
| | - W. Wasilewski
- Institute of Experimental Physics, University of Warsaw, Warsaw, Poland
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15
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He LY, Wang TJ, Wang C. Construction of high-dimensional universal quantum logic gates using a Λ system coupled with a whispering-gallery-mode microresonator. Opt Express 2016; 24:15429-15445. [PMID: 27410818 DOI: 10.1364/oe.24.015429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
High-dimensional quantum system provides a higher capacity of quantum channel, which exhibits potential applications in quantum information processing. However, high-dimensional universal quantum logic gates is difficult to achieve directly with only high-dimensional interaction between two quantum systems and requires a large number of two-dimensional gates to build even a small high-dimensional quantum circuits. In this paper, we propose a scheme to implement a general controlled-flip (CF) gate where the high-dimensional single photon serve as the target qudit and stationary qubits work as the control logic qudit, by employing a three-level Λ-type system coupled with a whispering-gallery-mode microresonator. In our scheme, the required number of interaction times between the photon and solid state system reduce greatly compared with the traditional method which decomposes the high-dimensional Hilbert space into 2-dimensional quantum space, and it is on a shorter temporal scale for the experimental realization. Moreover, we discuss the performance and feasibility of our hybrid CF gate, concluding that it can be easily extended to a 2n-dimensional case and it is feasible with current technology.
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16
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Saglamyurek E, Grimau Puigibert M, Zhou Q, Giner L, Marsili F, Verma VB, Woo Nam S, Oesterling L, Nippa D, Oblak D, Tittel W. A multiplexed light-matter interface for fibre-based quantum networks. Nat Commun 2016; 7:11202. [PMID: 27046076 DOI: 10.1038/ncomms11202] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 03/02/2016] [Indexed: 11/29/2022] Open
Abstract
Processing and distributing quantum information using photons through fibre-optic or free-space links are essential for building future quantum networks. The scalability needed for such networks can be achieved by employing photonic quantum states that are multiplexed into time and/or frequency, and light-matter interfaces that are able to store and process such states with large time-bandwidth product and multimode capacities. Despite important progress in developing such devices, the demonstration of these capabilities using non-classical light remains challenging. Here, employing the atomic frequency comb quantum memory protocol in a cryogenically cooled erbium-doped optical fibre, we report the quantum storage of heralded single photons at a telecom-wavelength (1.53 μm) with a time-bandwidth product approaching 800. Furthermore, we demonstrate frequency-multimode storage and memory-based spectral-temporal photon manipulation. Notably, our demonstrations rely on fully integrated quantum technologies operating at telecommunication wavelengths. With improved storage efficiency, our light-matter interface may become a useful tool in future quantum networks. Scalable networks for processing and distribution of quantum information using photons can be achieved by using multiplexed quantum states. Here, the authors report frequency-multimode storage and spectral-temporal photon manipulation of heralded single photons at telecom wavelength, in a fully integrated setting.
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17
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Zhou ZQ, Hua YL, Liu X, Chen G, Xu JS, Han YJ, Li CF, Guo GC. Quantum Storage of Three-Dimensional Orbital-Angular-Momentum Entanglement in a Crystal. Phys Rev Lett 2015; 115:070502. [PMID: 26317702 DOI: 10.1103/physrevlett.115.070502] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Indexed: 05/09/2023]
Abstract
Here we present the quantum storage of three-dimensional orbital-angular-momentum photonic entanglement in a rare-earth-ion-doped crystal. The properties of the entanglement and the storage process are confirmed by the violation of the Bell-type inequality generalized to three dimensions after storage (S=2.152±0.033). The fidelity of the memory process is 0.993±0.002, as determined through complete quantum process tomography in three dimensions. An assessment of the visibility of the stored weak coherent pulses in higher-dimensional spaces demonstrates that the memory is highly reliable for 51 spatial modes. These results pave the way towards the construction of high-dimensional and multiplexed quantum repeaters based on solid-state devices. The multimode capacity of rare-earth-based optical processors goes beyond the temporal and the spectral degree of freedom, which might provide a useful tool for photonic information processing.
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Affiliation(s)
- Zong-Quan Zhou
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yi-Lin Hua
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Xiao Liu
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Geng Chen
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Jin-Shi Xu
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yong-Jian Han
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Chuan-Feng Li
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Guang-Can Guo
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
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19
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Dajczgewand J, Le Gouët JL, Louchet-Chauvet A, Chanelière T. Large efficiency at telecom wavelength for optical quantum memories. Opt Lett 2014; 39:2711-2714. [PMID: 24784084 DOI: 10.1364/ol.39.002711] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We implement the ROSE protocol in an erbium-doped solid, compatible with the telecom range. The ROSE scheme is an adaptation of the standard two-pulse photon echo to make it suitable for a quantum memory. We observe a retrieval efficiency of 40% for a weak laser pulse in the forward direction by using specific orientations of the light polarizations, magnetic field, and crystal axes.
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Abstract
In this Letter, we propose a hybrid scheme to implement a photonic controlled-z (CZ) gate using photon storage in highly excited Rydberg states, which controls the effective photon-photon interaction using resonant microwave fields. Our scheme decouples the light propagation from the interaction and exploits the spatial properties of the dipole blockade phenomenon to realize a CZ gate with minimal loss and mode distortion. By excluding the coupling efficiency, fidelities exceeding 95% are achievable and are found to be mainly limited by motional dephasing and the finite lifetime of the Rydberg levels.
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Affiliation(s)
- D Paredes-Barato
- Joint Quantum Centre (JQC) Durham-Newcastle, Department of Physics, Durham University, Rochester Building, South Road, Durham DH1 3LE, United Kingdom
| | - C S Adams
- Joint Quantum Centre (JQC) Durham-Newcastle, Department of Physics, Durham University, Rochester Building, South Road, Durham DH1 3LE, United Kingdom
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21
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Zhou ZQ, Wang J, Li CF, Guo GC. Efficient spectral hole-burning and atomic frequency comb storage in Nd(3+):YLiF4. Sci Rep 2013; 3:2754. [PMID: 24067549 DOI: 10.1038/srep02754] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 09/06/2013] [Indexed: 11/09/2022] Open
Abstract
We present spectral hole-burning measurements of the 4I9/2 → 4F3/2 transition in Nd3+:YLiF4. The isotope shifts of Nd3+ can be directly resolved in the optical absorption spectrum. We report atomic frequency comb storage with an echo efficiency of up to 35% and a memory bandwidth of 60 MHz in this material. The interesting properties show the potential of this material for use in both quantum and classical information processing.
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Abstract
A light-storage experiment with a total (storage and retrieval) efficiency η=56% is carried out by enclosing a sample, with a single-pass absorption of 10%, in an impedance-matched cavity. The experiment is carried out using the atomic frequency comb (AFC) technique in a praseodymium-doped crystal (0.05%Pr(3+):Y2SiO5) and the cavity is created by depositing reflection coatings directly onto the crystal surfaces. The AFC technique has previously by far demonstrated the highest multimode capacity of all quantum memory concepts tested experimentally. We claim that the present work shows that it is realistic to create efficient, on-demand, long storage time AFC memories.
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Affiliation(s)
- Mahmood Sabooni
- Department of Physics, Lund University, P. O. Box 118, SE-22100 Lund, Sweden
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23
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Nunn J, Langford NK, Kolthammer WS, Champion TFM, Sprague MR, Michelberger PS, Jin XM, England DG, Walmsley IA. Enhancing multiphoton rates with quantum memories. Phys Rev Lett 2013; 110:133601. [PMID: 23581318 DOI: 10.1103/physrevlett.110.133601] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Indexed: 06/02/2023]
Abstract
Single photons are a vital resource for optical quantum information processing. Efficient and deterministic single photon sources do not yet exist, however. To date, experimental demonstrations of quantum processing primitives have been implemented using nondeterministic sources combined with heralding and/or postselection. Unfortunately, even for eight photons, the data rates are already so low as to make most experiments impracticable. It is well known that quantum memories, capable of storing photons until they are needed, are a potential solution to this "scaling catastrophe." Here, we analyze in detail the benefits of quantum memories for producing multiphoton states, showing how the production rates can be enhanced by many orders of magnitude. We identify the quantity ηB as the most important figure of merit in this connection, where η and B are the efficiency and time-bandwidth product of the memories, respectively.
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Affiliation(s)
- J Nunn
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
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24
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Chrapkiewicz R, Wasilewski W. Generation and delayed retrieval of spatially multimode Raman scattering in warm rubidium vapors. Opt Express 2012; 20:29540-29552. [PMID: 23388781 DOI: 10.1364/oe.20.029540] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We apply collective Raman scattering to create, store and retrieve spatially multimode light in warm rubidium-87 vapors. The light is created in a spontaneous Stokes scattering process. This is accompanied by the creation of counterpart collective excitations in the atomic ensemble - the spin waves. After a certain storage time we coherently convert the spin waves into the light in deterministic anti-Stokes scattering. The whole process can be regarded as a delayed four-wave mixing which produces pairs of correlated, delayed random images. Storage of higher order spatial modes up to microseconds is possible owing to usage of a buffer gas. We study the performance of the Raman scattering, storage and retrieval of collective excitations focusing on spatial effects and the influence of decoherence caused by diffusion of rubidium atoms in different buffer gases. We quantify the number of modes created and retrieved by analyzing statistical correlations of intensity fluctuations between portions of the light scattered in the far field.
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Simmons S, Wu H, Morton JJL. Controlling and exploiting phases in multi-spin systems using electron spin resonance and nuclear magnetic resonance. Philos Trans A Math Phys Eng Sci 2012; 370:4794-4809. [PMID: 22946041 DOI: 10.1098/rsta.2011.0354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The phase of a superposition state is a quintessential characteristic that differentiates a quantum bit of information from a classical one. This phase can be manipulated dynamically or geometrically, and can be exploited to sensitively estimate Hamiltonian parameters, perform faithful quantum state tomography and encode quantum information into multiple modes of an ensemble. Here we discuss the methods that we have employed to manipulate and exploit the phase information of single-, two-, multi-qubit and multi-mode spin systems.
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Affiliation(s)
- Stephanie Simmons
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
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Grodecka-Grad A, Zeuthen E, Sørensen AS. High-capacity spatial multimode quantum memories based on atomic ensembles. Phys Rev Lett 2012; 109:133601. [PMID: 23030088 DOI: 10.1103/physrevlett.109.133601] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Indexed: 06/01/2023]
Abstract
We study spatial multimode quantum memories based on light storage in extended ensembles of Λ-type atoms. We show that such quantum light-matter interfaces allow for highly efficient storage of many spatial modes. In particular, forward operating memories possess excellent scaling with the important physical parameters: quadratic scaling with the Fresnel number and even cubic with the optical depth of the atomic ensemble. Thus, the simultaneous use of both the longitudinal and transverse shape of the stored spin wave modes constitutes a valuable and so far overlooked resource for multimode quantum memories.
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Affiliation(s)
- Anna Grodecka-Grad
- QUANTOP, Danish National Research Foundation Center for Quantum Optics, Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen Ø, Denmark.
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Reim KF, Nunn J, Jin XM, Michelberger PS, Champion TFM, England DG, Lee KC, Kolthammer WS, Langford NK, Walmsley IA. Multipulse addressing of a Raman quantum memory: configurable beam splitting and efficient readout. Phys Rev Lett 2012; 108:263602. [PMID: 23004977 DOI: 10.1103/physrevlett.108.263602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Indexed: 06/01/2023]
Abstract
Quantum memories are vital to the scalability of photonic quantum information processing (PQIP), since the storage of photons enables repeat-until-success strategies. On the other hand, the key element of all PQIP architectures is the beam splitter, which allows us to coherently couple optical modes. Here, we show how to combine these crucial functionalities by addressing a Raman quantum memory with multiple control pulses. The result is a coherent optical storage device with an extremely large time bandwidth product, that functions as an array of dynamically configurable beam splitters, and that can be read out with arbitrarily high efficiency. Networks of such devices would allow fully scalable PQIP, with applications in quantum computation, long distance quantum communications and quantum metrology.
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Affiliation(s)
- K F Reim
- Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
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Dai HN, Zhang H, Yang SJ, Zhao TM, Rui J, Deng YJ, Li L, Liu NL, Chen S, Bao XH, Jin XM, Zhao B, Pan JW. Holographic storage of biphoton entanglement. Phys Rev Lett 2012; 108:210501. [PMID: 23003228 DOI: 10.1103/physrevlett.108.210501] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 03/20/2012] [Indexed: 06/01/2023]
Abstract
Coherent and reversible storage of multiphoton entanglement with a multimode quantum memory is essential for scalable all-optical quantum information processing. Although a single photon has been successfully stored in different quantum systems, storage of multiphoton entanglement remains challenging because of the critical requirement for coherent control of the photonic entanglement source, multimode quantum memory, and quantum interface between them. Here we demonstrate a coherent and reversible storage of biphoton Bell-type entanglement with a holographic multimode atomic-ensemble-based quantum memory. The retrieved biphoton entanglement violates the Bell inequality for 1 μs storage time and a memory-process fidelity of 98% is demonstrated by quantum state tomography.
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Affiliation(s)
- Han-Ning Dai
- Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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Affiliation(s)
- Dave Townsend
- School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom, and Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, K1A 0R6, Canada
| | - Benjamin J. Sussman
- School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom, and Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, K1A 0R6, Canada
| | - Albert Stolow
- School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom, and Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, K1A 0R6, Canada
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Wu H, George RE, Wesenberg JH, Mølmer K, Schuster DI, Schoelkopf RJ, Itoh KM, Ardavan A, Morton JJL, Briggs GAD. Storage of multiple coherent microwave excitations in an electron spin ensemble. Phys Rev Lett 2010; 105:140503. [PMID: 21230819 DOI: 10.1103/physrevlett.105.140503] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Indexed: 05/30/2023]
Abstract
Strong coupling between a microwave photon and electron spins, which could enable a long-lived quantum memory element for superconducting qubits, is possible using a large ensemble of spins. This represents an inefficient use of resources unless multiple photons, or qubits, can be orthogonally stored and retrieved. Here we employ holographic techniques to realize a coherent memory using a pulsed magnetic field gradient and demonstrate the storage and retrieval of up to 100 weak 10 GHz coherent excitations in collective states of an electron spin ensemble. We further show that such collective excitations in the electron spin can then be stored in nuclear spin states, which offer coherence times in excess of seconds.
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Affiliation(s)
- Hua Wu
- Department of Materials, Oxford University, Oxford OX1 3PH, United Kingdom
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31
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Sabooni M, Beaudoin F, Walther A, Lin N, Amari A, Huang M, Kröll S. Storage and recall of weak coherent optical pulses with an efficiency of 25%. Phys Rev Lett 2010; 105:060501. [PMID: 20867963 DOI: 10.1103/physrevlett.105.060501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Indexed: 05/29/2023]
Abstract
We demonstrate experimentally an efficient coherent rephasing scheme for the storage and recall of weak coherent light pulses in an inhomogeneously broadened optical transition in a Pr(3+):YSO crystal at 2.1 K. Precise optical pumping using a frequency stable (≈1 kHz linewidth) laser is employed to create a highly controllable atomic frequency comb structure. We report single photon level storage and retrieval efficiencies of 25%, based on coherent photon-echo-type reemission in the forward direction. The high efficiency is mainly a product of our highly controllable and precise ensemble-shaping technique. The coherence property of the quantum memory is proved through interference between a super-Gaussian pulse and the emitted echo.
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Affiliation(s)
- M Sabooni
- Department of Physics, Lund University, P.O. Box 118, SE-22100 Lund, Sweden
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Usmani I, Afzelius M, de Riedmatten H, Gisin N. Mapping multiple photonic qubits into and out of one solid-state atomic ensemble. Nat Commun 2010; 1. [DOI: 10.1038/ncomms1010] [Citation(s) in RCA: 157] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Accepted: 03/05/2010] [Indexed: 11/08/2022] Open
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Afzelius M, Usmani I, Amari A, Lauritzen B, Walther A, Simon C, Sangouard N, Minár J, de Riedmatten H, Gisin N, Kröll S. Demonstration of atomic frequency comb memory for light with spin-wave storage. Phys Rev Lett 2010; 104:040503. [PMID: 20366694 DOI: 10.1103/physrevlett.104.040503] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Indexed: 05/29/2023]
Abstract
We present a light-storage experiment in a praseodymium-doped crystal where the light is mapped onto an inhomogeneously broadened optical transition shaped into an atomic frequency comb. After absorption of the light, the optical excitation is converted into a spin-wave excitation by a control pulse. A second control pulse reads the memory (on-demand) by reconverting the spin-wave excitation to an optical one, where the comb structure causes a photon-echo-type rephasing of the dipole moments and directional retrieval of the light. This combination of photon-echo and spin-wave storage allows us to store submicrosecond (450 ns) pulses for up to 20 mus. The scheme has a high potential for storing multiple temporal modes in the single-photon regime, which is an important resource for future long-distance quantum communication based on quantum repeaters.
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Affiliation(s)
- Mikael Afzelius
- Group of Applied Physics, University of Geneva, CH-1211 Geneva 4, Switzerland.
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