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Related papers: Decoherence by engineered quantum baths

200 papers

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

Despite the importance of isotopically purified samples in current experiments, there have been few corresponding studies of spin qubit decoherence using full quantum bath calculations. Isotopic purification eliminates the well-studied…

Quantum Physics · Physics 2016-01-06 J. E. Lang , R. Guichard , S. J. Balian , T. S. Monteiro

For an electron spin in coupling with an interacting spin chain via hyperfine-type interaction, we investigate the dynamical evolutions of the pairwise entanglement of the spin chain and a correlation function joined the electron spin with…

Mesoscale and Nanoscale Physics · Physics 2012-02-15 Zhi-Hui Wang , Bing-Shen Wang , Zhao-Bin Su

We solve the time-dependent Schrodinger equation for the combination of a spin system interacting with a spin bath environment. In particular, we focus on the time development of the reduced density matrix of the spin system. Under normal…

Quantum Physics · Physics 2010-03-30 Shengjun Yuan , Mikhail I. Katsnelson , Hans De Raedt

The dynamics of two coupled spins-1/2 coupled to a spin-bath is studied as an extended model of the Tessieri-Wilkie Hamiltonian \cite{TWmodel}. The pair of spins served as an open subsystem were prepared in one of the Bell states and the…

Quantum Physics · Physics 2009-11-13 Jun Jing , H. R. Ma

We show that the coherence of an electron spin interacting with a bath of nuclear spins can exhibit a well-defined purely exponential decay for special (`narrowed') bath initial conditions in the presence of a strong applied magnetic field.…

Mesoscale and Nanoscale Physics · Physics 2008-04-07 W. A. Coish , Jan Fischer , Daniel Loss

For a central system uniformly coupled to a XY spin-1/2 bath in a transverse field, we explicitly calculate the Loschmidt echo(LE) to characterize decoherence quantitatively. We find that the anisotropy parameter $\gamma $ affects…

Quantum Physics · Physics 2009-11-13 Yong-Cheng Ou , Heng Fan

We study the temporal evolution of entanglement pertaining to two qubits interacting with a thermal bath. In particular we consider the simplest nontrivial spin bath models where symmetry breaking occurs and treat them by mean field…

Quantum Physics · Physics 2009-11-10 Marco Lucamarini , Simone Paganelli , Stefano Mancini

We study the interaction of a two-level atom and two fields, one of them classical. We obtain an effective Hamiltonian for this system by using a method recently introduced that produces a small rotation to the Hamiltonian that allows to…

Quantum Physics · Physics 2013-12-04 R. Juárez-Amaro , J. L. Escudero-Jiménez , H. Moya-Cessa

In this study, we propose a spin-star model for spin-(1/2) particles in order to examine the coherence dynamics of a quantum neural network (QNN) unit. Since quantum computing paradigm promises advantages over their classical counterparts,…

Quantum Physics · Physics 2019-05-03 Deniz Türkpençe , Tahir Çetin Akıncı , Serhat Şeker

We have recently shown that there is a limit to quantum coherence in many-particle spin qubits due to spontaneous symmetry breaking. These results were derived for the Lieb-Mattis spin model. Here we will show that the underlying mechanism…

Strongly Correlated Electrons · Physics 2009-11-11 Jasper van Wezel , Jan Zaanen , Jeroen van den Brink

We investigate the decoherence of a superposition of symmetric collective internal states of an atomic ensemble due to inhomogeneous coupling to external control fields. For asymptotically large system, we find the characteristic…

Quantum Physics · Physics 2009-11-07 C. P. Sun , S. Yi , L. You

We revisit the problem of the decoherence and relaxation of a central spin coupled to a bath of conduction electrons. We consider both metallic and semiconducting baths to study the effect of a gap in the bath density of states (DOS) on the…

Mesoscale and Nanoscale Physics · Physics 2013-04-16 Juliana Restrepo , R. Chitra , S. Camalet , Emilie Dupont

We study decoherence in an interacting qubit system described by infinite range Heisenberg model (IRHM) in a situation where the system is coupled to a bath of local optical phonons. Using perturbation theory in polaron frame of reference,…

Quantum Physics · Physics 2016-01-21 Muzaffar Qadir Lone , Sudhakar Yarlaggada

We consider the decoherence of a single localized electron spin due to its coupling to the lattice nuclear spin bath in a semiconductor quantum computer architecture. In the presence of an external magnetic field and at low temperatures,…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 W. M. Witzel , S. Das Sarma

We describe the decoherence process induced on a two-level quantum system in direct interaction with a non-equilibrium environment. The non-equilibrium feature is represented by a non-stationary random function corresponding to the…

Quantum Physics · Physics 2015-06-15 Fernando C. Lombardo , Paula I. Villar

We study the resilience of the surface code to decoherence caused by the presence of a bosonic bath. This approach allows us to go beyond the standard stochastic error model commonly used to quantify decoherence and error threshold…

Quantum Physics · Physics 2013-08-02 P. Jouzdani , E. Novais , E. R. Mucciolo

The Heisenberg model, a quantum mechanical analogue of the Ising model, has a large ground state degeneracy, due to the symmetry generated by the total spin. This symmetry is also responsible for degeneracies in the rest of the spectrum. We…

Condensed Matter · Physics 2009-10-22 A. J. van der Sijs

A perfect quantum state transfer(QST) has been shown in an engineered spin chain with "always-on interaction". Here, we consider a more realistic problem for such a protocol, the quantum decoherence induced by a spatially distributed…

Quantum Physics · Physics 2007-05-23 Lan Zhou , Jing Lu , Tao Shi , C. P. Sun

We consider environment induced decoherence of quantum superpositions to mixtures in the limit in which that process is much faster than any competing one generated by the Hamiltonian $H_{\rm sys}$ of the isolated system. While the golden…

Quantum Physics · Physics 2009-11-06 Daniel Braun , Fritz Haake , Walter T. Strunz