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It is known that a quantum system with finite degrees of freedom can simulate a composite of a system and an environment if the state of the hypothetical environment is randomized by external manipulation. We show theoretically that any…

A quantum system interacts with its environment, if ever so slightly, no matter how much care is put into isolating it. As a consequence, quantum bits (qubits) undergo errors, putting dauntingly difficult constraints on the hardware…

The dynamical properties of a quantum system can be profoundly influenced by its environment. Usually, the environment provokes decoherence and its action on the system can often be schematized by adding a noise term in the Hamiltonian.…

Quantum Physics · Physics 2015-06-26 S. Pascazio

To implement quantum information technologies, carefully designed control for preparing a desired state plays a key role. However, in realistic situation, the actual performance of those methodologies is severely limited by decoherence.…

Quantum Physics · Physics 2025-10-02 Kohei Kobayashi

We show that the methods for quantification of system-environment entanglement that were recently developed for interactions that lead to pure decoherence of the system can be straightforwardly generalized to time-dependent Hamiltonians of…

Quantum Physics · Physics 2025-04-01 Małgorzata Strzałka , Radim Filip , Katarzyna Roszak

According to Bell's theorem, the degree of correlation between spatially separated measurements on a quantum system is limited by certain inequalities if one assumes the condition of locality. Quantum mechanics predicts that this limit can…

Quantum Physics · Physics 2016-09-08 A. Venugopalan , Deepak Kumar , R. Ghosh

We investigate system-environment correlations based on the exact dynamics of a qubit and its environment in the framework of pure decoherence (phase damping). We focus on the relation of decoherence and the build-up of system-reservoir…

Quantum Physics · Physics 2013-05-29 A. Pernice , W. T. Strunz

We discuss decoherence due to electromagnetic fluctuations in charge qubits formed by two lateral quantum dots. We use an effective circuit model to evaluate correlations of voltage fluctuations in the qubit setup. These correlations allows…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Diego C. B. Valente , Eduardo R. Mucciolo , F. K. Wilhelm

We found that in contrast with the common premise, a measurement on the environment of an open quantum system can {\em reduce} its decoherence rate. We demonstrate it by studying an example of indirect qubit's measurement, where the…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Yin Ye , Yunshan Cao , Xin-Qi Li , Shmuel Gurvitz

With recent developments in high-precision quantum measurements, the question of whether observations of decoherence from spacetime fluctuations are accessible experimentally arises. Here we investigate the dynamics of bound states…

General Relativity and Quantum Cosmology · Physics 2017-06-06 Teodora Oniga , Charles H. -T. Wang

When modeling the effects of noise on quantum circuits, one often makes the assumption that these effects can be accounted for by individual decoherence events following an otherwise noise-free gate. In this work, we address the validity of…

Quantum Physics · Physics 2023-12-19 Keith R. Fratus , Juha Leppäkangas , Michael Marthaler , Jan-Michael Reiner

The dynamical evolution of a quantum register of arbitrary length coupled to an environment of arbitrary coherence length is predicted within a relevant model of decoherence. The results are reported for quantum bits (qubits) coupling…

Quantum Physics · Physics 2009-11-07 John H. Reina , Luis Quiroga , Neil F. Johnson

The detection and estimation of quantum entanglement are the essential issues in the theory of quantum entanglement. We construct matrices based on the realignment of density matrices and the vectorization of the reduced density matrices,…

Quantum Physics · Physics 2024-05-21 Jiaxin Sun , Hongmei Yao , Shao-Ming Fei , Zhaobing Fan

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

We investigate the capabilities of a quantum computer based on cold trapped ions in presence of non-dissipative decoherence. The latter is accounted by using the evolution time as a random variable and then averaging on a properly defined…

Quantum Physics · Physics 2009-11-06 Stefano Mancini , Rodolfo Bonifacio

We investigate decoherence channels that are modelled as a sequence of collisions of a quantum system (e.g., a qubit) with particles (e.g., qubits) of the environment. We show that collisions induce decoherence when a bi-partite interaction…

Quantum Physics · Physics 2009-11-11 Mario Ziman , Vladimir Buzek

Schemes of gravitationally induced decoherence are being actively investigated as possible mechanisms for the quantum-to-classical transition. Here, we introduce a decoherence process due to quantum gravity effects. We assume a foamy…

General Relativity and Quantum Cosmology · Physics 2021-07-23 Luciano Petruzziello , Fabrizio Illuminati

We show that the decoherence, which in the long run destroys quantum features of a system, can be used to reveal the entanglement in a two-qubit system. To this end, we consider a criterion that formally resembles the…

Quantum Physics · Physics 2018-09-07 Jan Krzywda , Piotr Szańkowski , Jan Chwedeńczuk , Łukasz Cywiński

For a system described by a multivariate probability density function obeying the fluctuation theorem, the average dissipation is lower-bounded by the degree of asymmetry of the marginal distributions (namely the relative entropy between…

Statistical Mechanics · Physics 2021-08-18 Michele Campisi , Lorenzo Buffoni

We study decoherence of two non-interacting qubits. The environment and its interaction with the qubits are modelled by random matrices. Decoherence, measured in terms of purity, is calculated in linear response approximation. Monte Carlo…

Quantum Physics · Physics 2007-11-22 C. Pineda , T. Gorin , T. H. Seligman