1
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Jing J, Wu LA. One-component quantum mechanics and dynamical leakage-free paths. Sci Rep 2022; 12:9247. [PMID: 35654980 PMCID: PMC9163118 DOI: 10.1038/s41598-022-13130-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 05/20/2022] [Indexed: 12/02/2022] Open
Abstract
We derive an exact one-component equation of motion for the probability amplitude of a target time-dependent state, and use the equation to reformulate quantum dynamics and control for both closed and open systems. Using the one-component equation, we show that an unexpected time-dependent leakage-free path can be induced and we capture a necessary quantity in determining the effect of decoherence suppression. Our control protocol based on the nonperturbative leakage elimination operator provides a unified perspective connecting some subtle, popular, and important concepts of quantum control, such as dynamical decoupling, quantum Zeno effect, and adiabatic passage. The resultant one-component equation will promise significant advantages in both quantum dynamics and control.
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Affiliation(s)
- Jun Jing
- Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Zhejiang University, Hangzhou, 310027, Zhejiang, China
| | - Lian-Ao Wu
- Department of Physics, The University of the Basque Country (EHU/UPV), P.O. Box 644, 48080, Bilbao, Spain.
- Ikerbasque, Basque Foundation for Science, 48011, Bilbao, Spain.
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2
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Markaida BG, Wu LA. Implementation of leakage elimination operators and subspace protection. Sci Rep 2020; 10:18846. [PMID: 33139762 PMCID: PMC7606502 DOI: 10.1038/s41598-020-75730-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 10/05/2020] [Indexed: 11/25/2022] Open
Abstract
Decoherence-induced leakage errors can potentially damage physical or logical qubits embedded in a subspace of the entire Hilbert space by coupling them to other system levels. Here we report the first experimental implementation of Leakage Elimination Operators (LEOs) that aims to reduce this undermining. LEOs are a type of dynamical decoupling control that have been previously introduced to counteract leakage from a chosen subspace into the rest of a Hilbert space, and have been widely explored theoretically. Different from other error correction strategies, LEOs are compatible with any gate sequence in a code space, and thus, compatible with universal quantum computation. Using IBM's cloud quantum computer (QC), we design three potentially applicable examples of subspaces in two- and three-qubit Hilbert spaces and derive the explicit forms of the corresponding LEOs for these subspaces. For the first time, we experimentally demonstrate that these LEOs significantly suppress leakage. The results also show that the LEO time-scale condition can be satisfied with noise in the IBM's cloud QC and pave a way for quantum setups to get rid of leakage trouble.
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Affiliation(s)
- B G Markaida
- Department of Theoretical Physics and History of Science, The Basque Country University (UPV/EHU), P.O. Box 644, 48080, Bilbao, Spain
| | - L-A Wu
- Department of Theoretical Physics and History of Science, The Basque Country University (UPV/EHU), P.O. Box 644, 48080, Bilbao, Spain.
- Ikerbasque, Basque Foundation for Science, 48011, Bilbao, Spain.
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3
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Mukherjee S, Mogilevtsev D, Slepyan GY, Doherty TH, Thomson RR, Korolkova N. Dissipatively coupled waveguide networks for coherent diffusive photonics. Nat Commun 2017; 8:1909. [PMID: 29199272 PMCID: PMC5712527 DOI: 10.1038/s41467-017-02048-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 11/03/2017] [Indexed: 11/18/2022] Open
Abstract
A photonic circuit is generally described as a structure in which light propagates by unitary exchange and transfers reversibly between channels. In contrast, the term ‘diffusive’ is more akin to a chaotic propagation in scattering media, where light is driven out of coherence towards a thermal mixture. Based on the dynamics of open quantum systems, the combination of these two opposites can result in novel techniques for coherent light control. The crucial feature of these photonic structures is dissipative coupling between modes, via an interaction with a common reservoir. Here, we demonstrate experimentally that such systems can perform optical equalisation to smooth multimode light, or act as a distributor, guiding it into selected channels. Quantum thermodynamically, these systems can act as catalytic coherent reservoirs by performing perfect non-Landauer erasure. For lattice structures, localised stationary states can be supported in the continuum, similar to compacton-like states in conventional flat-band lattices. Diffusive light propagation represents a valuable additional tool for integrated photonic technologies. As an example, here the authors experimentally demonstrate optical equalisation of coherent light propagating in a femtosecond laser written circuit which simulates a dissipatively-coupled quantum chain.
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Affiliation(s)
- Sebabrata Mukherjee
- Scottish Universities Physics Alliance (SUPA), Institute of Photonics and Quantum Sciences, School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - Dmitri Mogilevtsev
- Institute of Physics, Belarus National Academy of Sciences, F. Skarina Ave. 68, Minsk, 220072, Belarus.
| | - Gregory Ya Slepyan
- Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Thomas H Doherty
- School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS, UK
| | - Robert R Thomson
- Scottish Universities Physics Alliance (SUPA), Institute of Photonics and Quantum Sciences, School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Natalia Korolkova
- School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS, UK
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4
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Nemoto K, Devitt S, Munro WJ. Noise management to achieve superiority in quantum information systems. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2016.0236. [PMID: 28652492 PMCID: PMC5487715 DOI: 10.1098/rsta.2016.0236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/19/2017] [Indexed: 06/07/2023]
Abstract
Quantum information systems are expected to exhibit superiority compared with their classical counterparts. This superiority arises from the quantum coherences present in these quantum systems, which are obviously absent in classical ones. To exploit such quantum coherences, it is essential to control the phase information in the quantum state. The phase is analogue in nature, rather than binary. This makes quantum information technology fundamentally different from our classical digital information technology. In this paper, we analyse error sources and illustrate how these errors must be managed for the system to achieve the required fidelity and a quantum superiority.This article is part of the themed issue 'Quantum technology for the 21st century'.
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Affiliation(s)
- Kae Nemoto
- National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430, Japan
| | - Simon Devitt
- National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430, Japan
- Center for Emergent Matter Science, RIKEN, Wakoshi, Saitama 315-0198, Japan
| | - William J Munro
- National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430, Japan
- NTT BRL, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan
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5
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Ikuta R, Nozaki S, Yamamoto T, Koashi M, Imoto N. Experimental demonstration of robust entanglement distribution over reciprocal noisy channels assisted by a counter-propagating classical reference light. Sci Rep 2017; 7:4819. [PMID: 28684798 PMCID: PMC5500561 DOI: 10.1038/s41598-017-05008-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 05/23/2017] [Indexed: 11/30/2022] Open
Abstract
Embedding a quantum state in a decoherence-free subspace (DFS) formed by multiple photons is one of the promising methods for robust entanglement distribution of photonic states over collective noisy channels. In practice, however, such a scheme suffers from a low efficiency proportional to transmittance of the channel to the power of the number of photons forming the DFS. The use of a counter-propagating coherent pulse can improve the efficiency to scale linearly in the channel transmission, but it achieves only protection against phase noises. Recently, it was theoretically proposed [Phys. Rev. A 87, 052325(2013)] that the protection against bit-flip noises can also be achieved if the channel has a reciprocal property. Here we experimentally demonstrate the proposed scheme to distribute polarization-entangled photon pairs against a general collective noise including the bit flip noise and the phase noise. We observed an efficient sharing rate scaling while keeping a high quality of the distributed entangled state. Furthermore, we show that the method is applicable not only to the entanglement distribution but also to the transmission of arbitrary polarization states of a single photon.
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Affiliation(s)
- Rikizo Ikuta
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, 560-8531, Japan.
| | - Shota Nozaki
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, 560-8531, Japan
| | - Takashi Yamamoto
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, 560-8531, Japan
| | - Masato Koashi
- Photon Science Center, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Nobuyuki Imoto
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, 560-8531, Japan
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6
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Friesen M, Ghosh J, Eriksson MA, Coppersmith SN. A decoherence-free subspace in a charge quadrupole qubit. Nat Commun 2017; 8:15923. [PMID: 28643778 PMCID: PMC5490009 DOI: 10.1038/ncomms15923] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 05/15/2017] [Indexed: 12/03/2022] Open
Abstract
Quantum computing promises significant speed-up for certain types of computational problems. However, robust implementations of semiconducting qubits must overcome the effects of charge noise that currently limit coherence during gate operations. Here we describe a scheme for protecting solid-state qubits from uniform electric field fluctuations by generalizing the concept of a decoherence-free subspace for spins, and we propose a specific physical implementation: a quadrupole charge qubit formed in a triple quantum dot. The unique design of the quadrupole qubit enables a particularly simple pulse sequence for suppressing the effects of noise during gate operations. Simulations yield gate fidelities 10-1,000 times better than traditional charge qubits, depending on the magnitude of the environmental noise. Our results suggest that any qubit scheme employing Coulomb interactions (for example, encoded spin qubits or two-qubit gates) could benefit from such a quadrupolar design.
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Affiliation(s)
- Mark Friesen
- Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Joydip Ghosh
- Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - M. A. Eriksson
- Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - S. N. Coppersmith
- Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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7
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Koch CP. Controlling open quantum systems: tools, achievements, and limitations. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:213001. [PMID: 27143501 DOI: 10.1088/0953-8984/28/21/213001] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The advent of quantum devices, which exploit the two essential elements of quantum physics, coherence and entanglement, has sparked renewed interest in the control of open quantum systems. Successful implementations face the challenge of preserving relevant nonclassical features at the level of device operation. A major obstacle is decoherence, which is caused by interaction with the environment. Optimal control theory is a tool that can be used to identify control strategies in the presence of decoherence. Here we review recent advances in optimal control methodology that allow typical tasks in device operation for open quantum systems to be tackled and discuss examples of relaxation-optimized dynamics. Optimal control theory is also a useful tool to exploit the environment for control. We discuss examples and point out possible future extensions.
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Affiliation(s)
- Christiane P Koch
- Theoretische Physik, Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
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Xu JS, Yung MH, Xu XY, Tang JS, Li CF, Guo GC. Robust bidirectional links for photonic quantum networks. SCIENCE ADVANCES 2016; 2:e1500672. [PMID: 26824069 PMCID: PMC4730861 DOI: 10.1126/sciadv.1500672] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 09/07/2015] [Indexed: 05/28/2023]
Abstract
Optical fibers are widely used as one of the main tools for transmitting not only classical but also quantum information. We propose and report an experimental realization of a promising method for creating robust bidirectional quantum communication links through paired optical polarization-maintaining fibers. Many limitations of existing protocols can be avoided with the proposed method. In particular, the path and polarization degrees of freedom are combined to deterministically create a photonic decoherence-free subspace without the need for any ancillary photon. This method is input state-independent, robust against dephasing noise, postselection-free, and applicable bidirectionally. To rigorously quantify the amount of quantum information transferred, the optical fibers are analyzed with the tools developed in quantum communication theory. These results not only suggest a practical means for protecting quantum information sent through optical quantum networks but also potentially provide a new physical platform for enriching the structure of the quantum communication theory.
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Affiliation(s)
- Jin-Shi Xu
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, People’s Republic of China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Man-Hong Yung
- Department of Physics, South University of Science and Technology of China, Shenzhen 518055, People’s Republic of China
- Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 10084, People’s Republic of China
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Xiao-Ye Xu
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, People’s Republic of China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Jian-Shun Tang
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, People’s Republic of China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Chuan-Feng Li
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, People’s Republic of China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
| | - Guang-Can Guo
- Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026, People’s Republic of China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
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9
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Hou SY, Sheng YB, Feng GR, Long GL. Experimental optimal single qubit purification in an NMR quantum information processor. Sci Rep 2014; 4:6857. [PMID: 25358758 PMCID: PMC4215327 DOI: 10.1038/srep06857] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/13/2014] [Indexed: 11/09/2022] Open
Abstract
High quality single qubits are the building blocks in quantum information processing. But they are vulnerable to environmental noise. To overcome noise, purification techniques, which generate qubits with higher purities from qubits with lower purities, have been proposed. Purifications have attracted much interest and been widely studied. However, the full experimental demonstration of an optimal single qubit purification protocol proposed by Cirac, Ekert and Macchiavello [Phys. Rev. Lett. 82, 4344 (1999), the CEM protocol] more than one and half decades ago, still remains an experimental challenge, as it requires more complicated networks and a higher level of precision controls. In this work, we design an experiment scheme that realizes the CEM protocol with explicit symmetrization of the wave functions. The purification scheme was successfully implemented in a nuclear magnetic resonance quantum information processor. The experiment fully demonstrated the purification protocol, and showed that it is an effective way of protecting qubits against errors and decoherence.
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Affiliation(s)
- Shi-Yao Hou
- State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- The Innovative Center of Quantum Matter, Beijing 100084, China
- Tsinghua National Laboratory of Information Science and Technology, Beijing 100084, China
| | - Yu-Bo Sheng
- State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- Institute of Signal Processing Transmission, Nanjing University of Posts and Telecommunications, Nanjing, 210003, China
| | - Guan-Ru Feng
- State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- The Innovative Center of Quantum Matter, Beijing 100084, China
- Tsinghua National Laboratory of Information Science and Technology, Beijing 100084, China
| | - Gui-Lu Long
- State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China
- The Innovative Center of Quantum Matter, Beijing 100084, China
- Tsinghua National Laboratory of Information Science and Technology, Beijing 100084, China
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10
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Lidar DA. Review of Decoherence-Free Subspaces, Noiseless Subsystems, and Dynamical Decoupling. ADVANCES IN CHEMICAL PHYSICS 2014. [DOI: 10.1002/9781118742631.ch11] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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11
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Manzano G, Galve F, Giorgi GL, Hernández-García E, Zambrini R. Synchronization, quantum correlations and entanglement in oscillator networks. Sci Rep 2013; 3:1439. [PMID: 23486526 PMCID: PMC3596799 DOI: 10.1038/srep01439] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 02/18/2013] [Indexed: 11/25/2022] Open
Abstract
Synchronization is one of the paradigmatic phenomena in the study of complex systems. It has been explored theoretically and experimentally mostly to understand natural phenomena, but also in view of technological applications. Although several mechanisms and conditions for synchronous behavior in spatially extended systems and networks have been identified, the emergence of this phenomenon has been largely unexplored in quantum systems until very recently. Here we discuss synchronization in quantum networks of different harmonic oscillators relaxing towards a stationary state, being essential the form of dissipation. By local tuning of one of the oscillators, we establish the conditions for synchronous dynamics, in the whole network or in a motif. Beyond the classical regime we show that synchronization between (even unlinked) nodes witnesses the presence of quantum correlations and entanglement. Furthermore, synchronization and entanglement can be induced between two different oscillators if properly linked to a random network.
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Affiliation(s)
- Gonzalo Manzano
- Institute for Cross Disciplinary Physics and Complex Systems, IFISC (CSIC-UIB), Palma de Mallorca, Spain
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12
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Devitt SJ, Munro WJ, Nemoto K. Quantum error correction for beginners. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2013; 76:076001. [PMID: 23787909 DOI: 10.1088/0034-4885/76/7/076001] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Quantum error correction (QEC) and fault-tolerant quantum computation represent one of the most vital theoretical aspects of quantum information processing. It was well known from the early developments of this exciting field that the fragility of coherent quantum systems would be a catastrophic obstacle to the development of large-scale quantum computers. The introduction of quantum error correction in 1995 showed that active techniques could be employed to mitigate this fatal problem. However, quantum error correction and fault-tolerant computation is now a much larger field and many new codes, techniques, and methodologies have been developed to implement error correction for large-scale quantum algorithms. In response, we have attempted to summarize the basic aspects of quantum error correction and fault-tolerance, not as a detailed guide, but rather as a basic introduction. The development in this area has been so pronounced that many in the field of quantum information, specifically researchers who are new to quantum information or people focused on the many other important issues in quantum computation, have found it difficult to keep up with the general formalisms and methodologies employed in this area. Rather than introducing these concepts from a rigorous mathematical and computer science framework, we instead examine error correction and fault-tolerance largely through detailed examples, which are more relevant to experimentalists today and in the near future.
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Affiliation(s)
- Simon J Devitt
- National Institute of Informatics, 2-1-2 Hitotsubashi Chiyoda-ku Tokyo, 101-8340, Japan.
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13
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Sahrapour MM, Makri N. Tunneling, decoherence, and entanglement of two spins interacting with a dissipative bath. J Chem Phys 2013; 138:114109. [DOI: 10.1063/1.4795159] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Hsieh CY, Shim YP, Korkusinski M, Hawrylak P. Physics of lateral triple quantum-dot molecules with controlled electron numbers. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2012; 75:114501. [PMID: 23072742 DOI: 10.1088/0034-4885/75/11/114501] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We review the recent progress in theory and experiments with lateral triple quantum dots with controlled electron numbers down to one electron in each dot. The theory covers electronic and spin properties as a function of topology, number of electrons, gate voltage and external magnetic field. The orbital Hund's rules and Nagaoka ferromagnetism, magnetic frustration and chirality, interplay of quantum interference and electron-electron interactions and geometrical phases are described and related to charging and transport spectroscopy. Fabrication techniques and recent experiments are covered, as well as potential applications of triple quantum-dot molecule in coherent control, spin manipulation and quantum computation.
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Affiliation(s)
- Chang-Yu Hsieh
- Quantum Theory Group, Security and Disruptive Technologies, National Research Council, Ottawa, ON K1A 0R6, Canada
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15
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Kocherzhenko AA, Grozema FC, Siebbeles LDA. Single molecule charge transport: from a quantum mechanical to a classical description. Phys Chem Chem Phys 2011; 13:2096-110. [DOI: 10.1039/c0cp01432j] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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16
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17
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Lee JS, Regatte RR, Jerschow A. Optimal excitation of (23)Na nuclear spins in the presence of residual quadrupolar coupling and quadrupolar relaxation. J Chem Phys 2010; 131:174501. [PMID: 19895019 DOI: 10.1063/1.3253970] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Optimal control theory is applied for designing pulse sequences to optimally excite a spin-3/2 system with residual quadrupolar coupling in the presence of quadrupolar relaxation. A homogeneous form of the master equation is constructed to simulate the dynamics of the spin system, and a general optimization procedure with a homogeneous form of the equation of motion is described. The optimized pulses are tested with (23)Na NMR, and their performance is compared with that of pulses optimized in the absence of relaxation.
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Affiliation(s)
- Jae-Seung Lee
- Department of Chemistry, New York University, New York, New York 10003, USA
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18
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Ball JL, Banaszek K. Hybrid noiseless subsystems for quantum communication over optical fibres. ACTA ACUST UNITED AC 2005. [DOI: 10.1088/0305-4470/39/1/l01] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Facchi P, Marmo G, Pascazio S, Scardicchio A, Sudarshan ECG. Zeno dynamics and constraints. ACTA ACUST UNITED AC 2004. [DOI: 10.1088/1464-4266/6/6/006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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20
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Prauzner-Bechcicki JS. Two-mode squeezed vacuum state coupled to the common thermal reservoir. ACTA ACUST UNITED AC 2004. [DOI: 10.1088/0305-4470/37/15/l04] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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