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Related papers: Decoherence by a chaotic many-spin bath

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We consider a spin-$j$ particle coupled to a structured bath of bosonic modes that decay into thermal baths. We obtain an analytic expression for the reduced spin state and use it to investigate non-Markovian spin dynamics. In the heavily…

Quantum Physics · Physics 2022-04-06 Mattias T. Johnsson , Ben Q. Baragiola , Thomas Volz , Gavin K. Brennen

We study the onset of chaos and statistical relaxation in two isolated dynamical quantum systems of interacting spins-1/2, one of which is integrable and the other chaotic. Our approach to identifying the emergence of chaos is based on the…

Statistical Mechanics · Physics 2012-06-05 L. F. Santos , F. Borgonovi , F. M. Izrailev

A formalism for studying the dynamics of quantum systems embedded in classical spin baths is introduced. The theory is based on generalized antisymmetric brackets and predicts the presence of open-path off-diagonal geometric phases in the…

Quantum Physics · Physics 2016-10-21 Alessandro Sergi

We investigate the feasibility for the preservation of coherence and entanglement of one and two spin qubits coupled to an interacting quantum spin-1/2 chain within the dynamical decoupling (DD) scheme. The performance is examined by…

Quantum Physics · Physics 2015-05-20 Jun-Ting Kao , Jo-Tzu Hung , Pochung Chen , Chung-Yu Mou

The origin of continuous energy spectra in large disordered interacting quantum systems is one of the key unsolved problems in quantum physics. While small quantum systems with discrete energy levels are noiseless and stay coherent forever…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Emilio Cuevas , Mikhail Feigel'man , Lev Ioffe , Marc Mezard

I show that the decoherence in a system of $N$ degenerate two--level atoms interacting with a bosonic heat bath is for any number of atoms $N$ governed by a generalized Hamming distance (called ``decoherence metric'') between the superposed…

Quantum Physics · Physics 2009-11-11 Daniel Braun

We solve the long-standing central spin problem for a general set of inhomogeneous bath couplings and a large class of initial bath states. We compute the time evolution of the coherence of a central spin coupled to a spin bath by resumming…

Mesoscale and Nanoscale Physics · Physics 2012-10-09 Edwin Barnes , Łukasz Cywiński , S. Das Sarma

Avoiding the loss of coherence of quantum mechanical states is an important prerequisite for quantum information processing. Dynamical decoupling (DD) is one of the most effective experimental methods for maintaining coherence, especially…

Quantum Physics · Physics 2010-10-08 Gonzalo A. Alvarez , Ashok Ajoy , Xinhua Peng , Dieter Suter

Environment-induced decoherence has long been recognised as being of crucial importance in the study of chaos in quantum systems. In particular, the exact form and strength of the system-environment interaction play a major role in the…

Quantum Physics · Physics 2017-08-02 Jessica K. Eastman , Joseph J. Hope , André R. R. Carvalho

Decoherence is the major stumbling block in the realization of a large-scale quantum computer. Ingenious methods have been devised to overcome decoherence, but their success has been proven only for over-simplified models of…

Quantum Physics · Physics 2009-11-13 Andrew P. Hines , P. C. E. Stamp

An exactly solvable model for the decoherence of one and two-qubit states interacting with a spin-bath, in the presence of a time-dependent magnetic field is studied. The magnetic field is static along $\hat{z}$ direction and oscillatory in…

Quantum Physics · Physics 2011-06-10 D. D. Bhaktavatsala Rao

We study the ultimate limits to the decoherence rate associated with dephasing processes. Fluctuating chaotic quantum systems are shown to exhibit extreme decoherence, with a rate that scales exponentially with the particle number, thus…

Quantum Physics · Physics 2019-01-15 Zhenyu Xu , Luis Pedro García-Pintos , Aurélia Chenu , Adolfo del Campo

Different approaches in quantifying environmentally-induced decoherence are considered. We identify a measure of decoherence, derived from the density matrix of the system of interest, that quantifies the environmentally induced error,…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Arkady Fedorov , Leonid Fedichkin , Vladimir Privman

We study, in the paradigm of open quantum systems, the dynamics of quantum coherence of a static polarizable two-level atom which is coupled with a thermal bath of fluctuating electromagnetic field in the absence and presence of boundaries.…

Quantum Physics · Physics 2016-10-03 Xiaobao Liu , Zehua Tian , Jieci Wang , Jiliang Jing

We investigate the intricate dynamics of quantum coherence and non-classical correlations in a two-qubit open quantum system coupled to a squeezed thermal reservoir. By exploring the correlations between spatially separated qubits, we…

Quantum Physics · Physics 2026-02-24 Neha Pathania , Ramniwas Meena , Subhashish Banerjee

We numerically study quantum chaos properties of long-range XXZ dipolar Hamiltonian spin systems. Two geometries are considered: (i) an open chain with 19 spins, (ii) a face-centered cubic lattice with 14 spins. Energy level-spacing…

Quantum Physics · Physics 2017-11-07 Dhrubo Jyoti

The effect of a number of mechanisms designed to suppress decoherence in open quantum systems are studied with respect to their effectiveness at slowing down the loss of entanglement. The effect of photonic band-gap materials and frequency…

Quantum Physics · Physics 2013-07-09 Sandeep K Goyal , Subhashish Banerjee , Sibasish Ghosh

Decoherence of a center spin or qubit in a spin bath is essentially determined by the many-body bath evolution. We develop a cluster-correlation expansion (CCE) theory for the spin bath dynamics relevant to the qubit decoherence problem. A…

Mesoscale and Nanoscale Physics · Physics 2008-08-25 Wen Yang , Ren-bao Liu

We examine the effects of intra-environmental coupling on decoherence by constructing a low temperature spin--spin-bath model of an atomic impurity in a Debye crystal. The impurity interacts with phonons of the crystal through…

Quantum Physics · Physics 2009-11-07 L. Tessieri , J. Wilkie

With the purpose to reveal consistency between multiple quantum (MQ) coherences and entanglement, we investigate numerically the dynamics of these phenomena in one-dimensional linear chains and ring of nuclear spins 1/2 coupled by dipole…

Quantum Physics · Physics 2009-05-26 G. B. Furman , V. M. Meerovich , V. L. Sokolovsky