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Related papers: Decoherence processes of a quantum two-level syste…

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We consider a system of two spin-1/2 particles, initially in an entangled Bell state. If one of the particles is interacting with an environment (e.g. a collection of N independent spins), the two-particle system undergoes decoherence.…

Quantum Physics · Physics 2009-12-27 Fedor Levkovich-Maslyuk

Gauge/gravity duality applied to strongly interacting systems at finite density predicts a universal intermediate energy phase to which we refer as a semi-local quantum liquid. Such a phase is characterized by a finite spatial correlation…

High Energy Physics - Theory · Physics 2015-05-28 Nabil Iqbal , Hong Liu , Mark Mezei

Instead of the conventional construction of symmetric and antisymmetric states by abruptly projecting with the symmetrizer or antisymmetrizer, this paper investigates rapid but continuous symmetrization via environment-induced decoherence.…

Quantum Physics · Physics 2025-09-16 Allan Tameshtit

We study the decoherence properties of a two-level (qubit) system homogeneously coupled to an environmental many-body system at a quantum transition, considering both continuous and first-order quantum transitions. In particular, we…

Statistical Mechanics · Physics 2018-12-04 Ettore Vicari

We employ the Loschmidt Echo, i.e. the signal recovered after the reversal of an evolution, to identify and quantify the processes contributing to decoherence. This procedure, which has been extensively used in single particle physics, is…

Quantum Physics · Physics 2012-07-25 Pablo R. Zangara , Axel D. Dente , Patricia R. Levstein , Horacio M. Pastawski

We present a rigorous analysis of the phenomenon of decoherence for general N-level systems coupled to reservoirs of free massless bosonic fields. We apply our general results to the specific case of the qubit. Our approach does not involve…

Quantum Physics · Physics 2015-06-26 M. Merkli , I. M. Sigal , G. P. Berman

Spin relaxation in the impurity band of a 2D semiconductor with spin-split spectrum in the external magnetic field is considered. Several mechanisms of spin relaxation are shown to be relevant. The first one is attributed to phonon-assisted…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Ilya Lyubinskiy

We analyze the quantum process tomography (QPT) in the presence of decoherence, focusing on distinguishing local and non-local decoherence mechanisms for a two-partite system from experimental QPT data. In particular, we consider the…

Quantum Physics · Physics 2015-05-13 A. G. Kofman , A. N. Korotkov

We consider one source of decoherence for a single trapped ion due to intensity and phase fluctuations in the exciting laser pulses. For simplicity we assume that the stochastic processes involved are white noise processes, which enables us…

Quantum Physics · Physics 2009-10-30 S. Schneider , G. J. Milburn

We explore the physics of a spin-1/2 Heisenberg chain with Kondo interaction, $J_k$, to a two-dimensional electron gas. At weak $J_k$ the problem maps onto a Heisenberg chain locally coupled to a dissipative Ohmic bath. At the decoupled…

Strongly Correlated Electrons · Physics 2022-11-24 Bimla Danu , Matthias Vojta , Tarun Grover , Fakher F. Assaad

The long-time maintenance of quantum coherence is crucial for its practical applications. We explore decoherence process of a multiqubit system passing through a correlated channel (phase flip, bit flip, bit-phase flip, and depolarizing).…

Quantum Physics · Physics 2020-02-06 Ming-Liang Hu , Heng Fan

Quantum superpositions can be used for parallel information processing, but only if protected against decoherence. A two-particle four-state system may have two-dimensional subspaces that are partially or completely decoherence-free, e.g.,…

Quantum Physics · Physics 2007-05-23 Jeffrey Satinover

We investigate multipartite entanglement dynamics in disordered spin-1/2 lattice models exhibiting a transition from integrability to quantum chaos. Borrowing from the recently introduced generalized entanglement framework, we construct…

Quantum Physics · Physics 2009-11-11 Simone Montangero , Lorenza Viola

We study the scaling of decoherence of decoupled electron spin qubits due to hyperfine interaction. For a superposed state consisting of product states from a single Zeeman manifold, both $T_2^*(n)$ and $T_2(n)$ are scale-free with respect…

Quantum Physics · Physics 2015-03-02 Jun Jing , Xuedong Hu

We study systematically the non-Markovian decoherence dynamics of a dissipative two-level system, i.e., the so-called spin-boson model. It is interesting to find that the decoherence tends to be inhibited with the increase of the coupling…

Quantum Physics · Physics 2013-06-04 Hai-Bin Liu , Jun-Hong An , Chong Chen , Qing-Jun Tong , Hong-Gang Luo , C. H. Oh

We study the evolution of reduced density matrix of an impurity coupled to a Fermi sea after the coupling is switched on at time $t=0$. We find the non-diagonal elements of the reduced density matrix decay exponentially, and the decay…

Mesoscale and Nanoscale Physics · Physics 2011-02-02 Pei Wang

In a previous work [arXiv1905.01121] we have derived a quantum master equation for the dynamics of a scalar bosonic particle interacting with a weak, stochastic and classical gravitational field. As standard matter is made of fermions, such…

Quantum Physics · Physics 2021-07-21 Lorenzo Asprea , Giulio Gasbarri

Environment induced decoherence entails the absence of quantum interference phenomena from the macroworld. The loss of coherence between superposed wave packets depends on their separation. The precise temporal course depends on the…

Quantum Physics · Physics 2009-11-07 Walter T. Strunz , Fritz Haake

Computer simulations of decoherence in quantum spin systems require the solution of the time-dependent Schrodinger equation for interacting quantum spin systems over extended periods of time. We use exact diagonalization, Chebyshev…

Quantum Physics · Physics 2007-05-23 H. De Raedt , V. V. Dobrovitski

Half-metallicity (full spin polarization of the Fermi surface) usually occurs in strongly correlated electron systems. We demonstrate that doping a spin-density wave insulator in the weak-coupling regime may also stabilize half-metallic…

Strongly Correlated Electrons · Physics 2019-03-06 A. V. Rozhkov , A. L. Rakhmanov , A. O. Sboychakov , K. I. Kugel , F. Nori