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Related papers: Pure Phase Decoherence in a Ring Geometry

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The role of Aharonov-Bohm effect in quantum tunneling is examined when a potential is defined on the $S^1$ and has $N$-fold symmetry. We show that the low-lying energy levels split from the $N$-fold degenerate ground state oscillate as a…

Quantum Physics · Physics 2015-06-26 ChangSoo Park , D. K. Park

Dipoles interference is studied when atomic systems are coupled to classical electromagnetic fields. The interaction between the dipoles and the classical fields induces a time-varying Aharonov-Casher phase. Averaging over the phase…

Quantum Physics · Physics 2015-06-26 Fernando C. Lombardo , Francisco D. Mazzitelli , Paula I. Villar

We theoretically study the decoherence and the dynamical decoupling control of nitrogen-vacancy center electron spins in high-purity diamond, where the hyperfine interaction with $^{13}$C nuclear spins is the dominating decoherence…

Mesoscale and Nanoscale Physics · Physics 2015-03-19 Nan Zhao , Sai-Wah Ho , Ren-Bao Liu

We study the decoherence of two coupled spins that interact with a spin-bath environment. It is shown that the connectivity and the coupling strength between the spins in the environment are of crucial importance for the decoherence of the…

Quantum Physics · Physics 2008-10-22 Shengjun Yuan , Mikhail I. Katsnelson , Hans De Raedt

We study the chaotic scattering through an Aharonov-Bohm ring containing two cavities. One of the cavities has well-separated resonant levels while the other is chaotic, and is treated by random matrix theory. The conductance through the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Kazutaka Takahashi , Tomosuke Aono

We investigate the decoherence properties of a central system composed of two spins 1/2 in contact with a spin bath. The dynamical regime of the bath ranges from a fully integrable integrable limit to complete chaoticity. We show that the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 A. Relano , J. Dukelsky , R. A. Molina

Within quantum information frameworks, managing decoherence stands as a pivotal task. The present work delves into decoherence dynamics of a dressed qubit, represented by a spinless fermion hopping between two lattice sites that are…

Quantum Physics · Physics 2025-01-03 Saima Bashir , Muzaffar Qadir Lone , Prince A Ganai

We investigate the persistent current in a hybrid Aharonov-Bohm ring - quantum dot system coupled to a reservoir which provides spin fluctuations. It is shown that the spin exchange interaction between the quantum dot and the reservoir…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Kicheon Kang , Sam Young Cho , Kyoung Wan Park

The decoherence induced on a single qubit by its interaction with the environment is studied. The environment is modelled as a scalar two-level boson system that can go through either first order or continuous excited state quantum phase…

Quantum Physics · Physics 2015-05-14 P. Perez-Fernandez , A. Relano , J. M. Arias , J. Dukelsky , J. E. Garcia-Ramos

We investigate the nonequilibrium thermodynamics of pure decoherence. In a pure decoherence process, the system Hamiltonian is a constant of motion and there is no direct energy exchange between the system and its surroundings.…

Quantum Physics · Physics 2023-04-20 Maria Popovic , Mark T. Mitchison , John Goold

We study a model of dephasing (decoherence) in a two-state quantum system (qubit) coupled to a bath of harmonic oscillators. An exact analytic solution for the reduced dynamics of a two-state system in this model has been obtained…

Quantum Physics · Physics 2015-05-28 V. G. Morozov , S. Mathey , G. Röpke

We consider a SQUID tunneling between 2 nearly degenerate flux states. Decoherence caused by paramagnetic and nuclear spins in the low-$T$ limit is shown to be much stronger than that from electronic excitations. The decoherence time…

Condensed Matter · Physics 2007-05-23 Nikolay Prokof'ev , Philip Stamp

The superconducting flux qubit has two quantum states with opposite magnetic flux. Environment of nuclear spins can find out the direction of the magnetic flux after a decoherence time $\tau_0$ inversely proportional to the magnitude of the…

Other Condensed Matter · Physics 2009-11-10 Jacek Dziarmaga

The dynamics of an active walker in a harmonic potential is studied experimentally, numerically and theoretically. At odds with usual models of self-propelled particles, we identify two dynamical states for which the particle condensates at…

Soft Condensed Matter · Physics 2019-02-20 Olivier Dauchot , Vincent Démery

We consider qubits in a linear arrangement coupled to a bosonic field which acts as a quantum heat bath and causes decoherence. By taking the spatial separation of the qubits explicitly into account, the reduced qubit dynamics acquires an…

Mesoscale and Nanoscale Physics · Physics 2007-07-19 Roland Doll , Martijn Wubs , Peter Hanggi , Sigmund Kohler

We take a negative delta function impurity in one arm of a quasi one dimensional Aharonov-Bohm ring and demonstrate abrupt phase changes across a quasi bound state of the negative delta function potential. We give a new mechanism for…

Mesoscale and Nanoscale Physics · Physics 2008-02-03 P. Singha Deo

We calculate the oscillations of the DC conductance across a mesoscopic ring, simultaneously tuned by applied magnetic and electric fields orthogonal to the ring. The oscillations depend on the Aharonov-Bohm flux and of the spin-orbit…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 R. Capozza , D. Giuliano , P. Lucignano , A. Tagliacozzo

We examine the influence of environmental interactions on simple quantum systems by obtaining the exact reduced dynamics of a qubit coupled to a one-dimensional spin bath. In contrast to previous studies, both the qubit-bath coupling and…

Quantum Physics · Physics 2014-06-17 Ning Wu , Arun Nanduri , Herschel Rabitz

We study the closed Hamiltonian dynamics of a free particle moving on a ring, over one section of which it interacts linearly with a single harmonic oscillator. On the basis of numerical and analytical evidence, we conjecture that at small…

Chaotic Dynamics · Physics 2007-05-23 Stephan De Bievre , Paul E. Parris , Alex A. Silvius

The model of a ring threaded by the Aharonov-Bohm flux underlies our understanding of a coupling between gauge potentials and matter. The typical formulation of the model is based upon a single particle picture, and should be extended when…

Quantum Gases · Physics 2023-08-29 Fabian Brauneis , Areg Ghazaryan , Hans-Werner Hammer , Artem G. Volosniev