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Related papers: Decoherence and Entanglement Dynamics of Coupled Q…

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In a two-qubit system the coupling with an environment affects considerably the entanglement dynamics, and usually leads to the loss of entanglement within a finite time. Since entanglement is a key feature in the application of such…

Quantum Physics · Physics 2009-11-13 Y. Dubi , M. Di Ventra

Quantum mechanical entanglement can exist in noisy open quantum systems at high temperature. A simple mechanism, where system particles are randomly reset to some standard initial state, can counteract the deteriorating effect of…

Quantum Physics · Physics 2007-08-07 L. Hartmann , W. Dür , H. -J. Briegel

The conditions under which an open quantum mechanical system may be described by mixed quantum-classical dynamics are investigated. Decoherence is studied using influence functional methods in a model composite quantum system comprising two…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Kazutomu Shiokawa , Raymond Kapral

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

A standard theory of thermodynamics states that a quantum system in contact with a thermal environment relaxes to the equilibrium state known as the Gibbs state wherein decoherence occurs in the system's energy eigenbasis. When the…

Quantum Physics · Physics 2020-10-20 Patrick Lee Orman , Ryoichi Kawai

We investigate the influence of nearby two-level systems on the dynamics of a qubit. The intrinsic decoherence is given by a coupling of both the qubit and the two-level systems to a heat bath. Assuming weak interactions between the qubit…

Statistical Mechanics · Physics 2007-05-23 P. Nalbach

We obtain exact dynamics of a two-qubit central spin model (CSM) consisting of two interacting qubits homogeneously coupled to a spin bath via the $XXZ$-type coupling, with the bath initially prepared in linear superpositions of the…

Quantum Physics · Physics 2020-09-17 Zejiang Li , Pei Yang , Wen-Long You , Ning Wu

We analyse the dynamics of quantum correlations between two qubits coupled to a linear chain of oscillators. The chain mediates interactions between the qubits and acts as a non-Markovian reservoir. The the model is amenable to an…

Quantum Physics · Physics 2023-11-21 Sayan Roy , Christian Otto , Raphaël Menu , Giovanna Morigi

We demonstrate an exact mapping of a class of models of two interacting qubits in thermal reservoirs to two separate spin-bath problems. Based on this mapping, exact numerical simulations of the qubits dynamics can be performed, beyond the…

Quantum Physics · Physics 2015-06-05 Lian-Ao Wu , Claire X. Yu , Dvira Segal

We study the dynamics of entanglement of two electron spins in two quantum dots, in which each electron is interacting with its nuclear spin environment. Focusing on the case of uncoupled dots, and starting from either Bell or Werner states…

Mesoscale and Nanoscale Physics · Physics 2015-05-08 Igor Bragar , Łukasz Cywiński

We examine the decoherence of an asymmetric two-qubit system that is coupled via a tunable interaction term to a common bath or two individual baths of harmonic oscillators. The dissipative dynamics are evaluated using the Bloch-Redfield…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Markus J. Storcz , Frank Hellmann , Calin Hrelescu , Frank K. Wilhelm

We report on the immersion of a spin-qubit encoded in a single trapped ion into a spin-polarized neutral atom environment, which possesses both continuous (motional) and discrete (spin) degrees of freedom. The environment offers the…

Quantum Physics · Physics 2014-07-24 L. Ratschbacher , C. Sias , L. Carcagni , J. M. Silver , C. Zipkes , M. Köhl

We study a generic open quantum system where the coupling between the system and its environment is of an energy-preserving quantum nondemolition (QND) type. We obtain the general master equation for the evolution of such a system under the…

Quantum Physics · Physics 2007-10-02 Subhashish Banerjee , R. Ghosh

We investigate how two spatially separated qubits coupled to a common heat bath can be entangled by purely dissipative dynamics. We identify a dynamical time scale associated with the lifetime of the dissipatively generated entanglement and…

Quantum Physics · Physics 2013-05-29 Dara P. S. McCutcheon , Ahsan Nazir , Sougato Bose , Andrew J. Fisher

An exact reduced dynamical map along with its operator sum representation is derived for a central spin interacting with a thermal spin environment. The dynamics of the central spin shows high sustainability of quantum traits such as…

Quantum Physics · Physics 2017-11-23 Chiranjib Mukhopadhyay , Samyadeb Bhattacharya , Avijit Misra , Arun Kumar Pati

We use the quantum jump approach to study the entanglement dynamics of a quantum register, which is composed of two or three dipole-dipole coupled two-level atoms, interacting with a common environment. Our investigation of entanglement…

Quantum Physics · Physics 2009-11-13 Jun-Hong An , Shun-Jin Wang , Hong-Gang Luo

We study measures of decoherence and thermalization of a quantum system $S$ in the presence of a quantum environment (bath) $E$. The whole system is prepared in a canonical thermal state at a finite temperature. Applying perturbation theory…

Statistical Mechanics · Physics 2016-03-23 M. A. Novotny , F. Jin , S. Yuan , S. Miyashita , H. De Raedt , K. Michielsen

In this work we study the dynamics of the maximum extractable entanglement for a system composed of two qubits interacting either with two independent thermal baths, a common thermal bath or a common squeezed bath. The states with maximum…

Quantum Physics · Physics 2009-11-13 E. Isasi , D. Mundarain , J. Stephany

We consider spatially separated qubits coupled to a thermal bosonic field that causes pure dephasing. Our focus is on the entanglement of two Bell states which for vanishing separation are known as robust and fragile entangled states. The…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Roland Doll , Martijn Wubs , Peter Hanggi , Sigmund Kohler

We examine a two-qubit system influenced by a time-periodic external field while interacting with a Markovian bath. This scenario significantly impacts the temporal coherence characteristics of the system. By solving the evolution equation…

Quantum Physics · Physics 2023-12-19 Kirill Shulga