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We numerically investigate decoherence of a two-spin system (central system) by a bath of many spins 1/2. By carefully adjusting parameters, the dynamical regime of the bath has been varied from quantum chaos to regular, while all other…

Quantum Physics · Physics 2009-11-10 J. Lages , V. V. Dobrovitski , B. N. Harmon

We compare decoherence induced in a simple quantum system (qubit) for two different initial states of the environment: canonical (fixed temperature) and microcanonical (fixed energy), for the general case of a fully interacting oscillator…

Quantum Physics · Physics 2009-11-07 S. Khlebnikov , G. Sadiek

The effects of disorder and chaos on quantum many-body systems can be superficially similar, yet their interplay has not been sufficiently explored. This work finds a continuous phase transition when disorder breaks permutation symmetry,…

Quantum Physics · Physics 2026-05-28 Manju C , Arul Lakshminarayan , Uma Divakaran

We develop a mathematical description of the decoherence caused by "spin baths", such as nuclear spins or magnetic impurities. In contrast to the usual oscillator bath models of quantum environments, decoherence in the spin bath can occur…

Condensed Matter · Physics 2007-05-23 N. V. Prokof'ev , P. C. E. Stamp

Under natural conditions, excitation of biological molecules, which display non-unitary open system dynamics, occurs via incoherent processes such as temperature changes or irradiation by sunlight/moonlight. The dynamics of such processes…

Quantum Physics · Physics 2013-02-11 Leonardo A. Pachon , Paul Brumer

Recent experimental results point to the existence of coherent quantum phenomena in systems made of a large number of particles, despite the fact that for many-body systems the presence of decoherence is hardly negligible and emerging…

Quantum Physics · Physics 2017-09-21 F. Benatti , F. Carollo , R. Floreanini , H. Narnhofer

A general theory of electronic excitations in aggregates of molecules coupled to intramolecular vibrations and the harmonic environment is developed for simulation of the third-order nonlinear spectroscopy signals. The model is applied in…

Chemical Physics · Physics 2014-01-17 Vytautas Butkus , Leonas Valkunas , Darius Abramavicius

Control of decoherence in open quantum systems has become a topic of great interest due to the emergence of quantum technologies that depend on quantum coherent effects. In this work, we investigate the decoherence dynamics of systems…

Quantum Physics · Physics 2025-04-04 Jitian Chen , Jakub Garwoła , Dvira Segal

The character of evolution of an open quantum system is often encoded in the correlation function of the environment or, equivalently, in the spectral density function of the interaction. When the environment is heterogeneous, e.g. consists…

Quantum Physics · Physics 2021-01-20 V. A. Mikhailov , N. V. Troshkin

We discuss the influence of a zero-temperature environment on a coherent quantum system. First, we calculate the reduced density operator of the system in the framework of the well-known, exactly solvable model of an oscillator coupled to a…

Quantum Physics · Physics 2009-11-10 A. Ratchov , F. Faure , F. W. J. Hekking

We examine the dependence of decoherence on the spectral density of the environment as well as on the initial state of the system. We use two simple examples to illustrate some important effects. The simplest derivation of the general form…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Juan Pablo Paz

The interplay between quantum and thermal fluctuations in the presence of quenched random disorder is a long-standing open theoretical problem which has been made more urgent by advances in modern experimental techniques. The fragility of…

Strongly Correlated Electrons · Physics 2025-01-28 Matthew C. O'Brien , Eduardo Fradkin

Decoherence is the phenomenon of non-unitary dynamics that arises as a consequence of coupling between a system and its environment. It has important harmful implications for quantum information processing, and various solutions to the…

Quantum Physics · Physics 2022-09-21 Daniel A. Lidar , K. Birgitta Whaley

Environmental decoherence occurs when a quantum system interacts with its surroundings, progressively reducing quantum interference and coherence, complicating the preservation of critical quantum properties over time, especially during…

Quantum Physics · Physics 2025-12-18 Naeem Akhtar , Jia-Xin Peng , Tan Hailin , Xiaosen Yang , Dong Wang

We discuss how a background bath of gravitons can induce decoherence of quantum systems. The mechanism is dephasing, the loss of phase coherence due to quantum geometry fluctuations caused by the gravitons. This effect is illustrated in a…

General Relativity and Quantum Cosmology · Physics 2015-03-05 V. A. De Lorenci , L. H. Ford

It is known that the origin of the deviations from standard thermodynamics proceed from the strong coupling to the bath. Here, it is shown that these deviations are related to the power spectrum of the bath. Specifically, it is shown that…

Quantum Physics · Physics 2015-08-26 Johan F. Triana

The practical success of quantum technology hinges on sustaining quantum coherence, which is vulnerable to environmental interactions causing decoherence. We investigate coherence in tripartite quantum systems under the influence of noisy…

Quantum Physics · Physics 2026-03-16 Sovik Roy , Aahaman Kalaiselvan , Chandrashekar Radhakrishnan , Md Manirul Ali

Most discussions of decoherence in the literature consider the high-temperature regime but it is also known that, in the presence of dissipation, decoherence can occur even at zero temperature. Whereas most previous investigations all…

Quantum Physics · Physics 2009-11-10 G. W. Ford , R. F. O'Connell

The influence of the initial preparation on dephasing in open quantum dynamics is studied using an exactly solvable model of a two-level system (qubit) interacting with a bosonic bath. It is found that for some classes of non-selective…

Quantum Physics · Physics 2015-06-11 V. V. Ignatyuk , V. G. Morozov

Decoherence is one of the most important obstacles that must be overcome in quantum information processing. It depends on the qubit-environment coupling strength, but also on the spectral composition of the noise generated by the…

Quantum Physics · Physics 2011-12-02 Gonzalo A. Alvarez , Dieter Suter