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We analyze the decoherence of charge states in double quantum dots due to cotunneling. The system is treated using the Bloch-Redfield generalized master equation for the Schrieffer-Wolff transformed Hamiltonian. We show that the…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Udo Hartmann , Frank K. Wilhelm

The propagation of polarized photons in optical media can be effectively modeled by means of quantum dynamical semigroups. These generalized time evolutions consistently describe phenomena leading to loss of phase coherence and dissipation…

Quantum Physics · Physics 2009-11-07 F. Benatti , R. Floreanini

The aim of this review is to show how ``ferromagnetic'' states, that is, states having a fully polarization, can produce intrinsic decoherence by unitary evolution. This effect can give an understanding of recent experiments on mesoscopic…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Marco Frasca

We study theoretically how decoherence affects superposition states composed of entangled states in inductively coupled two superconducting flux-qubits. We discover that the quantum fluctuation of an observable in a coupled flux-qubit…

Mesoscale and Nanoscale Physics · Physics 2009-09-29 Takuya Mouri , Hayato Nakano , Hideaki Takayanagi

The interplay between dissipation and internal interactions in quantum many-body systems gives rise to a wealth of novel phenomena. Here we investigate spin-1/2 chains with uniform local couplings to a Markovian environment using the…

Strongly Correlated Electrons · Physics 2013-10-24 Zi Cai , Thomas Barthel

Quantum states inevitably decay with time into a probabilistic mixture of classical states, due to their interaction with the environment and measurement instrumentation. We present the first measurement of the decoherence dynamics of…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 H. Wang , M. Hofheinz , M. Ansmann , R. C. Bialczak , Erik Lucero , M. Neeley , A. D. O'Connell , D. Sank , M. Weides , J. Wenner , A. N. Cleland , John M. Martinis

The simple stationary decoherence of a two-state quantum system is discussed from a new viewpoint of environmental entanglement. My work emphasizes that an unconditional local state must totally be disentangled from the rest of the…

Quantum Physics · Physics 2022-09-21 Lajos Diosi

We numerically model the evolution of a pair of coherently split quasicondensates. A truly one-dimensional case is assumed, so that the loss of the (initially high) coherence between the two quasicondensates is due to dephasing only, but…

Quantum Gases · Physics 2011-11-16 H. -P. Stimming , N. J. Mauser , J. Schmiedmayer , I. E. Mazets

Based on the non-autonomous quantum master equation, we investigate the dissipative and decoherence properties of the two-level atom system interacting with the environment of thermal quantum radiation fields. For this system, by a novel…

Quantum Physics · Physics 2009-11-11 Shun-Jin Wang , Jun-Hong An , Hong-Gang Luo , Cheng-Long Jia

We establish quantum thermodynamics for open quantum systems weakly coupled to their reservoirs when the system exhibits degeneracies. The first and second law of thermodynamics are derived, as well as a finite-time fluctuation theorem for…

Statistical Mechanics · Physics 2017-03-08 Gregory Bulnes Cuetara , Massimiliano Esposito , Gernot Schaller

We investigate interplay between external field and interatomic interaction and its applications to coherent control of quantum tunneling for two repulsive bosons confined in a high-frequency driven double well. A full solution of the…

Quantum Physics · Physics 2015-06-15 Juan Liu , Wenhua Hai , Zheng Zhou

Decoherence of a quantum state coupled to an exterior environment is at the foundation of our understanding of the emergence of classical behavior from the quantum world, but how does it emerge in a finite closed quantum system? Here this…

Quantum Physics · Physics 2015-06-16 O. Fialko

We investigate decoherence-free evolution (DFE) of quantum discord (QD) for two initially-correlated qubits in two finite-temperature reservoirs using an exactly solvable model. We study QD dynamics of the two qubits coupled to two…

Quantum Physics · Physics 2011-02-15 Lan Xu , Ji-Bing Yuan , Qing-Shou Tan , Lan Zhou , Le-Man Kuang

The decoherence induced on a single qubit by its interaction with the environment is studied. The environment is modelled as a scalar two-level boson system that can go through either first order or continuous excited state quantum phase…

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

Although coupling to a super-Ohmic bosonic reservoir leads only to partial dephasing on short time scales, exponential decay of coherence appears in the Markovian limit (for long times) if anharmonicity of the reservoir is taken into…

Quantum Physics · Physics 2007-05-23 Paweł Machnikowski

Relaxation effects impose fundamental limitations on our ability to coherently control quantum mechanical phenomena. In this letter, we establish physical limits on how closely can a quantum mechanical system be steered to a desired target…

Quantum Physics · Physics 2009-11-10 N. Khaneja , B. Luy , S. J. Glaser

Quantum systems are affected by interactions with their environments, causing decoherence through two processes: pure dephasing and energy relaxation. For quantum information processing it is important to increase the coherence time of…

Quantum Physics · Physics 2018-03-21 Roberto Stassi , Franco Nori

We show that the unitary evolution of a harmonic oscillator coupled to a two-level system can be undone by a suitable manipulation of the two-level system -- more specifically: by a quasi-instantaneous phase change. This enables us to…

Quantum Physics · Physics 2010-03-26 Giovanna Morigi , Enrique Solano , Berthold-Georg Englert , Herbert Walther

We revisit the problem of switching off unwanted phase evolution and decoherence in a single two-state quantum system in the light of recent results on random dynamical decoupling methods [L. Viola and E. Knill, Phys. Rev. Lett. {\bf 94},…

Quantum Physics · Physics 2009-11-11 Lea F. Santos , Lorenza Viola

We present an approach that allows quantifying decoherence processes in an open quantum system subject to external time-dependent control. Interactions with the environment are modeled by a standard bosonic heat bath. We develop two…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Dmitry Solenov , Vladimir Privman