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Thiel H, Jehle L, Chapman RJ, Frick S, Conradi H, Kleinert M, Suchomel H, Kamp M, Höfling S, Schneider C, Keil N, Weihs G. Time-bin entanglement at telecom wavelengths from a hybrid photonic integrated circuit. Sci Rep 2024; 14:9990. [PMID: 38693329 PMCID: PMC11063055 DOI: 10.1038/s41598-024-60758-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 04/26/2024] [Indexed: 05/03/2024] Open
Abstract
Mass-deployable implementations for quantum communication require compact, reliable, and low-cost hardware solutions for photon generation, control and analysis. We present a fiber-pigtailed hybrid photonic circuit comprising nonlinear waveguides for photon-pair generation and a polymer interposer reaching 68 dB of pump suppression and photon separation based on a polarizing beam splitter with > 25 dB polarization extinction ratio. The optical stability of the hybrid assembly enhances the quality of the entanglement, and the efficient background suppression and photon routing further reduce accidental coincidences. We thus achieve a96 - 8 + 3 % concurrence and a96 - 5 + 2 % fidelity to a Bell state. The generated telecom-wavelength, time-bin entangled photon pairs are ideally suited for distributing Bell pairs over fiber networks with low dispersion.
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Affiliation(s)
- Hannah Thiel
- Institut für Experimentalphysik, Universität Innsbruck, 6020, Innsbruck, Austria.
| | - Lennart Jehle
- Faculty of Physics and Vienna Doctoral School in Physics and Vienna Center for Quantum Science and Technology, University of Vienna, 1090, Vienna, Austria
- Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut, 10587, Berlin, Germany
| | - Robert J Chapman
- Institut für Experimentalphysik, Universität Innsbruck, 6020, Innsbruck, Austria
- Department of Physics, Optical Nanomaterial Group, Institute for Quantum Electronics, ETH Zurich, 8093, Zurich, Switzerland
| | - Stefan Frick
- Institut für Experimentalphysik, Universität Innsbruck, 6020, Innsbruck, Austria
| | - Hauke Conradi
- Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut, 10587, Berlin, Germany
| | - Moritz Kleinert
- Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut, 10587, Berlin, Germany
| | - Holger Suchomel
- Technische Physik, Universität Würzburg, 97074, Würzburg, Germany
| | - Martin Kamp
- Technische Physik, Universität Würzburg, 97074, Würzburg, Germany
| | - Sven Höfling
- Technische Physik, Universität Würzburg, 97074, Würzburg, Germany
| | - Christian Schneider
- Technische Physik, Universität Würzburg, 97074, Würzburg, Germany
- Institute of Physics, University of Oldenburg, 26129, Oldenburg, Germany
| | - Norbert Keil
- Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut, 10587, Berlin, Germany
| | - Gregor Weihs
- Institut für Experimentalphysik, Universität Innsbruck, 6020, Innsbruck, Austria
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2
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Is Heralded Two-Photon Excited Fluorescence with Single Absorbers Possible with Current Technology? PHOTONICS 2022. [DOI: 10.3390/photonics9020052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The interaction between single or a fixed number of photons with a single absorber is of fundamental interest in quantum technology. The harnessing of light matter interactions at the single particle limit has several potential applications ranging from quantum communication and quantum metrology to quantum imaging. In this perspective, a setup for heralded two-photon excited fluorescence at the single absorber level is proposed. The setup is based on a heralded two-photon source utilizing spontaneous parametric down-conversion, entanglement swapping and sum frequency generation for joint detection. This perspective aimed at triggering a discussion about the study of TPA and TPEF with only very few photons. The feasibility of the scheme is assessed by estimating the performance based on state-of-the-art technologies and losses, with the conclusion that the realization appears to be very challenging, but not completely impossible.
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Anwar A, Perumangatt C, Steinlechner F, Jennewein T, Ling A. Entangled photon-pair sources based on three-wave mixing in bulk crystals. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:041101. [PMID: 34243479 DOI: 10.1063/5.0023103] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 03/01/2021] [Indexed: 06/13/2023]
Abstract
Entangled photon pairs are a critical resource in quantum communication protocols ranging from quantum key distribution to teleportation. The current workhorse technique for producing photon pairs is via spontaneous parametric down conversion (SPDC) in bulk nonlinear crystals. The increased prominence of quantum networks has led to a growing interest in deployable high performance entangled photon-pair sources. This manuscript provides a review of the state-of-the-art bulk-optics-based SPDC sources with continuous wave pump and discusses some of the main considerations when building for deployment.
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Affiliation(s)
- Ali Anwar
- Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, S117543 Singapore, Singapore
| | - Chithrabhanu Perumangatt
- Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, S117543 Singapore, Singapore
| | - Fabian Steinlechner
- Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Albert-Einstein-Straße 7, 07745 Jena, Germany
| | - Thomas Jennewein
- Institute of Quantum Computing and Department of Physics and Astronomy, University of Waterloo, 200 University Ave. W, Waterloo, Ontario N2L 3G1, Canada
| | - Alexander Ling
- Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, S117543 Singapore, Singapore
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Yang Q, Passow T. Non-ideal quarter-wavelength Bragg-reflection waveguides for nonlinear interaction: eigen equation and tolerance. OPTICS LETTERS 2020; 45:4742-4745. [PMID: 32870846 DOI: 10.1364/ol.397198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
A general eigen equation has been deduced that can handle ideal and non-ideal quarter-wavelength cases of Bragg-reflection waveguide structure for nonlinear interaction with matching layers on each side of the active region. In particular, this equation allows for solving the cases when the Bragg reflectors are non-ideal quarter-wavelength thick. With this equation, we propose a Bragg-reflection waveguide structure based on the AlxGa1-xAs/GaAs material system with high figure-of-merit |ξdeff| total nonlinearity and checked the influence if the thickness of the quarter-wavelength Bragg reflectors is off by 10%.
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Flamini F, Spagnolo N, Sciarrino F. Photonic quantum information processing: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:016001. [PMID: 30421725 DOI: 10.1088/1361-6633/aad5b2] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Photonic quantum technologies represent a promising platform for several applications, ranging from long-distance communications to the simulation of complex phenomena. Indeed, the advantages offered by single photons do make them the candidate of choice for carrying quantum information in a broad variety of areas with a versatile approach. Furthermore, recent technological advances are now enabling first concrete applications of photonic quantum information processing. The goal of this manuscript is to provide the reader with a comprehensive review of the state of the art in this active field, with a due balance between theoretical, experimental and technological results. When more convenient, we will present significant achievements in tables or in schematic figures, in order to convey a global perspective of the several horizons that fall under the name of photonic quantum information.
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Affiliation(s)
- Fulvio Flamini
- Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
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6
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Svozilík J, Peřina J, León-Montiel RDJ. Two-photon absorption spectroscopy using intense phase-chirped entangled beams. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.05.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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7
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Caspani L, Xiong C, Eggleton BJ, Bajoni D, Liscidini M, Galli M, Morandotti R, Moss DJ. Integrated sources of photon quantum states based on nonlinear optics. LIGHT, SCIENCE & APPLICATIONS 2017; 6:e17100. [PMID: 30167217 PMCID: PMC6062040 DOI: 10.1038/lsa.2017.100] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 05/28/2017] [Accepted: 06/02/2017] [Indexed: 05/21/2023]
Abstract
The ability to generate complex optical photon states involving entanglement between multiple optical modes is not only critical to advancing our understanding of quantum mechanics but will play a key role in generating many applications in quantum technologies. These include quantum communications, computation, imaging, microscopy and many other novel technologies that are constantly being proposed. However, approaches to generating parallel multiple, customisable bi- and multi-entangled quantum bits (qubits) on a chip are still in the early stages of development. Here, we review recent advances in the realisation of integrated sources of photonic quantum states, focusing on approaches based on nonlinear optics that are compatible with contemporary optical fibre telecommunications and quantum memory platforms as well as with chip-scale semiconductor technology. These new and exciting platforms hold the promise of compact, low-cost, scalable and practical implementations of sources for the generation and manipulation of complex quantum optical states on a chip, which will play a major role in bringing quantum technologies out of the laboratory and into the real world.
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Affiliation(s)
- Lucia Caspani
- Institute of Photonics, Department of Physics, University of Strathclyde, Glasgow G1 1RD, UK
- Institute of Photonics and Quantum Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK
| | - Chunle Xiong
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, NSW 2006, Australia
| | - Benjamin J Eggleton
- Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, Sydney, NSW 2006, Australia
| | - Daniele Bajoni
- Dipartimento di Ingegneria Industriale e dell’Informazione, Università di Pavia, via Ferrata 1, 27100, Pavia, Italy
| | - Marco Liscidini
- Dipartimento di Fisica, Università di Pavia, via Bassi 6, 27100 Pavia, Italy
| | - Matteo Galli
- Dipartimento di Fisica, Università di Pavia, via Bassi 6, 27100 Pavia, Italy
| | - Roberto Morandotti
- INRS-EMT, 1650 Boulevard Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China
- National Research University of Information Technologies, Mechanics and Optics, St. Petersburg, Russia
| | - David J Moss
- Center for Microphotonics, Swinburne University of Technology, Hawthorn, Victoria, 3122 Australia
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Orieux A, Versteegh MAM, Jöns KD, Ducci S. Semiconductor devices for entangled photon pair generation: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2017; 80:076001. [PMID: 28346219 DOI: 10.1088/1361-6633/aa6955] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Entanglement is one of the most fascinating properties of quantum mechanical systems; when two particles are entangled the measurement of the properties of one of the two allows the properties of the other to be instantaneously known, whatever the distance separating them. In parallel with fundamental research on the foundations of quantum mechanics performed on complex experimental set-ups, we assist today with bourgeoning of quantum information technologies bound to exploit entanglement for a large variety of applications such as secure communications, metrology and computation. Among the different physical systems under investigation, those involving photonic components are likely to play a central role and in this context semiconductor materials exhibit a huge potential in terms of integration of several quantum components in miniature chips. In this article we review the recent progress in the development of semiconductor devices emitting entangled photons. We will present the physical processes allowing the generation of entanglement and the tools to characterize it; we will give an overview of major recent results of the last few years and highlight perspectives for future developments.
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Affiliation(s)
- Adeline Orieux
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire d'Informatique de Paris 6 (LIP6), 4 Place Jussieu, 75005 Paris, France. IRIF UMR 8243, Université Paris Diderot, Sorbonne Paris Cité, CNRS, 75013 Paris, France
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Schlager A, Pressl B, Laiho K, Suchomel H, Kamp M, Höfling S, Schneider C, Weihs G. Temporally versatile polarization entanglement from Bragg reflection waveguides. OPTICS LETTERS 2017; 42:2102-2105. [PMID: 28569855 DOI: 10.1364/ol.42.002102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 05/03/2017] [Indexed: 06/07/2023]
Abstract
Bragg reflection waveguides emitting broadband parametric downconversion (PDC) have been proven to be well suited for the on-chip generation of polarization entanglement in a straightforward fashion [Sci. Rep.3, 2314 (2013)SRWSDA2045-232210.1038/srep02314]. Here, we investigate how the properties of the created states can be modified by controlling the relative temporal delay between the pair of photons created via PDC. Our results offer an easily accessible approach for changing the coherence of the polarization entanglement, in other words, to tune the phase of the off-diagonal elements of the density matrix. Furthermore, we provide valuable insight into the engineering of these states directly at the source.
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Laiho K, Pressl B, Schlager A, Suchomel H, Kamp M, Höfling S, Schneider C, Weihs G. Uncovering dispersion properties in semiconductor waveguides to study photon-pair generation. NANOTECHNOLOGY 2016; 27:434003. [PMID: 27659042 DOI: 10.1088/0957-4484/27/43/434003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We investigate the dispersion properties of ridge Bragg-reflection waveguides to deduce their phasematching characteristics. These are crucial for exploiting them as sources of parametric down-conversion (PDC). In order to estimate the phasematching bandwidth we first determine the group refractive indices of the interacting modes via Fabry-Perot experiments in two distant wavelength regions. Second, by measuring the spectra of the emitted PDC photons, we gain access to their group index dispersion. Our results offer a simple approach for determining the PDC process parameters in the spectral domain, and provide important feedback for designing such sources, especially in the broadband case.
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Affiliation(s)
- K Laiho
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
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11
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Pressl B, Günthner T, Laiho K, Geßler J, Kamp M, Höfling S, Schneider C, Weihs G. Mode-resolved Fabry-Perot experiment in low-loss Bragg-reflection waveguides. OPTICS EXPRESS 2015; 23:33608-33621. [PMID: 26832025 DOI: 10.1364/oe.23.033608] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Based on the interaction between different spatial modes, semiconductor Bragg-reflection waveguides (BRWs) provide a highly functional platform for non-linear optics. For achieving any desired quantum optical functionality, we must control and engineer the properties of each spatial mode. To reach this purpose we extend the Fabry-Perot technique and achieve a detailed linear optical characterization of dispersive multimode semiconductor waveguides. With this efficient broadband spectral method we gain direct experimental access to the relevant modes of our BRWs and determine their group velocities. Furthermore, we show that our waveguides have lower than expected loss coefficients. This renders them suitable for integrated quantum optics applications.
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12
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Takesue H, Matsuda N, Kuramochi E, Munro WJ, Notomi M. An on-chip coupled resonator optical waveguide single-photon buffer. Nat Commun 2014; 4:2725. [PMID: 24217422 PMCID: PMC3831293 DOI: 10.1038/ncomms3725] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 10/08/2013] [Indexed: 12/02/2022] Open
Abstract
Integrated quantum optical circuits are now seen as one of the most promising approaches with which to realize single-photon quantum information processing. Many of the core elements for such circuits have been realized, including sources, gates and detectors. However, a significant missing function necessary for photonic quantum information processing on-chip is a buffer, where single photons are stored for a short period of time to facilitate circuit synchronization. Here we report an on-chip single-photon buffer based on coupled resonator optical waveguides (CROW) consisting of 400 high-Q photonic crystal line-defect nanocavities. By using the CROW, a pulsed single photon is successfully buffered for 150 ps with 50-ps tunability while maintaining its non-classical properties. Furthermore, we show that our buffer preserves entanglement by storing and retrieving one photon from a time-bin entangled state. This is a significant step towards an all-optical integrated quantum information processor. Photonic circuits are a promising route to developing scalable quantum technologies, if all the necessary components can be built. Using coupled resonator optical waveguides, Takesue et al. present an on-chip single-photon buffer that can delay one photon from a pair for 150 ps while preserving entanglement.
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Affiliation(s)
- Hiroki Takesue
- NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan
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Mariani S, Andronico A, Lemaître A, Favero I, Ducci S, Leo G. Second-harmonic generation in AlGaAs microdisks in the telecom range. OPTICS LETTERS 2014; 39:3062-3065. [PMID: 24978274 DOI: 10.1364/ol.39.003062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on second-harmonic generation in whispering-gallery-mode AlGaAs microcavities suspended on a GaAs pedestal. Frequency doubling of a 1.58 μm pump is observed with 7×10(-4) W(-1) conversion efficiency. This device can be integrated in a monolithic photonic chip for classical and quantum applications in the telecom band.
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Boitier F, Orieux A, Autebert C, Lemaître A, Galopin E, Manquest C, Sirtori C, Favero I, Leo G, Ducci S. Electrically injected photon-pair source at room temperature. PHYSICAL REVIEW LETTERS 2014; 112:183901. [PMID: 24856696 DOI: 10.1103/physrevlett.112.183901] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Indexed: 06/03/2023]
Abstract
One of the main challenges for future quantum information technologies is the miniaturization and integration of high performance components in a single chip. In this context, electrically driven sources of nonclassical states of light have a clear advantage over optically driven ones. Here we demonstrate the first electrically driven semiconductor source of photon pairs working at room temperature and telecom wavelengths. The device is based on type-II intracavity spontaneous parametric down-conversion in an AlGaAs laser diode and generates pairs at 1.57 μm. Time-correlation measurements of the emitted pairs give an internal generation efficiency of 7×10(-11) pairs/injected electron. The capability of our platform to support the generation, manipulation, and detection of photons opens the way to the demonstration of massively parallel systems for complex quantum operations.
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Affiliation(s)
- Fabien Boitier
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
| | - Adeline Orieux
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
| | - Claire Autebert
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
| | - Aristide Lemaître
- Laboratoire de Photonique et Nanostructures, CNRS-UPR20, Route de Nozay, 91460 Marcoussis, France
| | - Elisabeth Galopin
- Laboratoire de Photonique et Nanostructures, CNRS-UPR20, Route de Nozay, 91460 Marcoussis, France
| | - Christophe Manquest
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
| | - Carlo Sirtori
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
| | - Ivan Favero
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
| | - Giuseppe Leo
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
| | - Sara Ducci
- Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot, Sorbonne Paris Cité, CNRS-UMR 7162, Case courrier 7021, 75205 Paris Cedex 13, France
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Inherent polarization entanglement generated from a monolithic semiconductor chip. Sci Rep 2014; 3:2314. [PMID: 23896982 PMCID: PMC3727056 DOI: 10.1038/srep02314] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/12/2013] [Indexed: 11/17/2022] Open
Abstract
Creating miniature chip scale implementations of optical quantum information protocols is a dream for many in the quantum optics community. This is largely because of the promise of stability and scalability. Here we present a monolithically integratable chip architecture upon which is built a photonic device primitive called a Bragg reflection waveguide (BRW). Implemented in gallium arsenide, we show that, via the process of spontaneous parametric down conversion, the BRW is capable of directly producing polarization entangled photons without additional path difference compensation, spectral filtering or post-selection. After splitting the twin-photons immediately after they emerge from the chip, we perform a variety of correlation tests on the photon pairs and show non-classical behaviour in their polarization. Combined with the BRW's versatile architecture our results signify the BRW design as a serious contender on which to build large scale implementations of optical quantum processing devices.
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