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Related papers: Decoherence in two coupled qubits

200 papers

We study a pair of capacitively coupled singlet-triplet spin qubits. We characterize the two-qubit decoherence through two complementary measures, the decay time of coupled-qubit oscillations and the fidelity of entangled state preparation.…

Mesoscale and Nanoscale Physics · Physics 2017-10-11 Yang-Le Wu , S. Das Sarma

Decoherence in quantum bit circuits is presently a major limitation to their use for quantum computing purposes. We present experiments, inspired from NMR, that characterise decoherence in a particular superconducting quantum bit circuit,…

Superconductivity · Physics 2015-06-25 G. Ithier , E. Collin , P. Joyez , P. J. Meeson , D. Vion , D. Esteve , F. Chiarello , A. Shnirman , Y. Makhlin , J. Schriefl , G. Schon

The dynamics of a qubit coupled with a quantum oscillator is re-studied in the region of strong coupling. The non-degenerate perturbation is added to the usual degenerate one and new results are given.

Quantum Physics · Physics 2012-09-04 Guihua Tian

Despite an apparent progress in implementing individual solid-state qubits, there have been no experimental reports so far on multi-bit gates required for building a real quantum computer. Here we report a new circuit comprising two coupled…

Mesoscale and Nanoscale Physics · Physics 2010-04-20 Yu. A. Pashkin , T. Yamamoto , O. Astafiev , Y. Nakamura , D. V. Averin , J. S. Tsai

Quantum decoherence has been studied using nuclear magnetic resonance(NMR). By choosing one qubit to simulate environment, we examine the decoherence behavior of two quantum systems: a one qubit system and a two qubit system. The…

Quantum Physics · Physics 2007-05-23 Jingfu Zhang , Zhiheng Lu , Lu Shan , Zhiwei Deng

We study dynamics of nonclassical correlations by exactly solving a model consisting of two atomic qubits with spontaneous emission. We find that the nonclassical correlations defined by different measures give different qualitative…

Quantum Physics · Physics 2012-02-01 Ming-Liang Hu , Heng Fan

This paper studies the energy decoherence of an interacting quantum system. It first reviews the experiments that motivated the postulates of quantum mechanics. It then discusses a decoherence that occurs dynamically in a closed system.…

Quantum Physics · Physics 2024-12-03 Henry Crumley

Interaction of solid state qubits with environmental degrees of freedom strongly affects the qubit dynamics, and leads to decoherence. In quantum information processing with solid state qubits, decoherence significantly limits the…

Mesoscale and Nanoscale Physics · Physics 2010-02-26 Luca Chirolli , Guido Burkard

We study decoherence of propagating spin-1/2 excitations in generic (non-integrable and/or disordered) spin chains. We find the relevant decoherence times to be shorter in both the near-critical and diffusive regimes (if any), which fact…

Strongly Correlated Electrons · Physics 2009-11-10 D. V. Khveshchenko

We analyze the decoherence induced on a single qubit by the interaction with a two-level boson system with critical internal dynamics. We explore how the decoherence process is affected by the presence of quantum phase transitions in the…

Quantum Physics · Physics 2015-05-14 A. Relano , J. M. Arias , J. Dukelsky , J. E. Garcia-Ramos , P. Perez-Fernandez

We study a model of dephasing (decoherence) in a two-state quantum system (qubit) coupled to a bath of harmonic oscillators. An exact analytic solution for the reduced dynamics of a two-state system in this model has been obtained…

Quantum Physics · Physics 2015-05-28 V. G. Morozov , S. Mathey , G. Röpke

Proposals for scalable quantum computing devices suffer not only from decoherence due to the interaction with their environment, but also from severe engineering constraints. Here we introduce a practical solution to these major concerns,…

Quantum Physics · Physics 2009-11-07 Mark S. Byrd , Daniel A. Lidar

Realising scalable quantum networks requires a meticulous level of understanding and mitigating the deleterious effects of decoherence. Many quantum device platforms feature multiple decoherence mechanisms, often with a dominant mechanism…

Quantum Physics · Physics 2023-08-17 Julian Wiercinski , Erik M. Gauger , Moritz Cygorek

The use of qubits as sensitive magnetometers has been studied theoretically and recent demonstrated experimentally. In this paper we propose a generalisation of this concept, where a scanning two-state quantum system is used to probe the…

Quantum Physics · Physics 2009-12-10 J. H. Cole , L. C. L. Hollenberg

We summarize our results on decoherence for short- to intermediate-time dynamics of an externally controlled two-state quantum system - a qubit - interacting with thermal bosonic environment. The developed approximation schemes are…

Quantum Physics · Physics 2010-09-22 Vladimir Privman , Dmitry Solenov

Decoherence in quantum computer memory due to the inevitable coupling to the external environment is examined. We take the assumption that all quantum bits (qubits) interact with the same environment rather than the assumption of separate…

Quantum Physics · Physics 2009-10-30 Lu-Ming Duan , Guang-Can Guo

Quantum decoherence happens when the system interacts with the environment. Quantum correlation behaviours in the two-qubit spin squeezing model are studied under the influence of intrinsic decoherence. Quantitative results were determined,…

Quantum Physics · Physics 2023-03-07 Venkat Abhignan , R. Muthuganesan

Coherent interaction of a quantum system with environment usually induces quantum decoherence. However, remarkably, in certain configurations the coherent system-environment coupling can be simultaneously explored to engineer a specific…

Complexity in strongly correlated electron systems is analyzed by considering decoherence process between the localized state, |L> and the itinerant state, |I>. The coherent superposition state of a|I> + b|L> decoheres to the pointer states…

Strongly Correlated Electrons · Physics 2011-01-04 Byung Gyu Chae

Decoherence of a solid state based qubit can be caused by coupling to microscopic degrees of freedom in the solid. We lay out a simple theory and use it to estimate decoherence for a recently proposed superconducting persistent current…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Lin Tian , L. S. Levitov , Caspar H. van der Wal , J. E. Mooij , T. P. Orlando , S. Lloyd , C. J. P. M. Harmans , J. J. Mazo