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Related papers: Spin relaxation and decoherence of two-level syste…

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Spin squeezing of a nonlinear interaction model with Josephson-like coupling is studied to obtain time scale of maximal squeezing. Based upon two exactly solvable cases for two and three particles, we find that the maximal-squeezing time…

Quantum Physics · Physics 2011-11-10 Guang-Ri Jin , Sang Wook Kim

We study the dynamics of entanglement in spin gases. A spin gas consists of a (large) number of interacting particles whose random motion is described classically while their internal degrees of freedom are described quantum-mechanically.…

Quantum Physics · Physics 2007-05-23 J. Calsamiglia , L. Hartmann , W. Dür , H. -J. Briegel

We propose a scheme to manipulate the spin coherence in vertically coupled GaAs double quantum dots. Up to {\em ten} orders of magnitude variation of the spin relaxation and {\em two} orders of magnitude variation of the spin dephasing can…

Materials Science · Physics 2008-03-19 Y. Y. Wang , M. W. Wu

We examine an exactly solvable model of decoherence - a spin-system interacting with a collection of environment spins. We show that in this model (introduced some time ago to illustrate environment-induced superselection) generic…

Quantum Physics · Physics 2013-05-29 W. H. Zurek , F. M. Cucchietti , J. P. Paz

We study the time evolution of a single spin coupled inhomogeneously to a spin environment. Such a system is realized by a single electron spin bound in a semiconductor nanostructure and interacting with surrounding nuclear spins. We find…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 John Schliemann , Alexander V. Khaetskii , Daniel Loss

We discuss the rate of relaxation of the total spin in the two-electron droplet in the vicinity of the magnetic field driven singlet-triplet transition. The total spin relaxation is attributed to spin-orbit and electron-phonon interactions.…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 S. Dickmann , P. Hawrylak

We solve for the decoherence dynamics of two models in which a simple qubit or Central Spin couples to a bath of spins; the bath is made from a chain of spins. In model 1, the bath spins are Ising spins; in Model 2, they are coupled by…

Quantum Physics · Physics 2024-05-08 P. C. E. Stamp Zhen Zhu

The works on decoherence due to spin baths usually agree in studying a one-spin system in interaction with a large spin bath. In this paper we generalize those models by analyzing a many-spin system and by studying decoherence or its…

Quantum Physics · Physics 2010-01-21 Mario Castagnino , Sebastian Fortin , Olimpia Lombardi

We review recent studies on spin decoherence of electrons and holes in quasi-two-dimensional quantum dots, as well as electron-spin relaxation in nanowire quantum dots. The spins of confined electrons and holes are considered major…

Mesoscale and Nanoscale Physics · Physics 2009-07-28 Jan Fischer , Mircea Trif , W. A. Coish , Daniel Loss

We study the decoherence dynamics of dipole-coupled two-level quantum systems in Ramsey-type experiments. We focus on large networks of two-level systems, confined to two spatial dimensions and with positional disorder giving rise to…

Quantum Gases · Physics 2017-11-15 M. P. Kwasigroch , N. R. Cooper

We review the problem of spin decoherence of magnetic atoms deposited on a surface. Recent breakthroughs in scanning tunnelling microscopy (STM) make it possible to probe the spin dynamics of individual atoms, either isolated or integrated…

Mesoscale and Nanoscale Physics · Physics 2017-02-14 F. Delgado , J. Fernández-Rossier

We present a general unifying theory for spin polarization decay due to the interplay of spin precession and momentum scattering that is applicable to both spin-1/2 electrons and spin-3/2 holes. Our theory allows us to identify and…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Dimitrie Culcer , Roland Winkler

The dominant source of decoherence for an electron spin in a quantum dot is the hyperfine interaction with the surrounding bath of nuclear spins. The decoherence process may be slowed down by subjecting the electron spin to suitable…

Mesoscale and Nanoscale Physics · Physics 2017-08-23 Wenxian Zhang , V. V. Dobrovitski , Lea F. Santos , Lorenza Viola , B. N. Harmon

We consider the common spin-1/2 XX-model in one dimension with open boundary conditions and a large but finite number of spins. The system is in thermal equilibrium at times t<0, and is subject to a weak local perturbation (quantum quench)…

Statistical Mechanics · Physics 2025-02-27 Peter Reimann , Christian Eidecker-Dunkel

This paper describes the dynamics of a quantum two-level system (qubit) under the influence of an environment modeled by an ensemble of random matrices. In distinction to earlier work, we consider here separable couplings and focus on a…

Quantum Physics · Physics 2015-06-19 M. Carrera , T. Gorin , T. H. Seligman

The description of the dynamics of closed quantum systems, governed by the Schroedinger equation at first sight seems incompatible with the Lindblad equation describing open ones. By analyzing closed dynamics of a spin-1/2 chain we…

Quantum Physics · Physics 2011-08-30 Marcin Wieśniak

The dynamics of a spin-1/2 particle coupled to a nuclear spin bath through an isotropic Heisenberg interaction is studied, as a model for the spin decoherence in quantum dots. The time-dependent polarization of the central spin is…

Quantum Physics · Physics 2007-06-28 D. D. Bhaktavatsala Rao , V. Ravishankar , V. Subrahmanyam

We study the ordering of the spin and the chirality in the fully frustrated XY model on a square lattice by extensive Monte Carlo simulations. Our results indicate unambiguously that the spin and the chirality exhibit separate phase…

Statistical Mechanics · Physics 2015-05-19 Soichirou Okumura , Hajime Yoshino , Hikaru Kawamura

We study systematically the non-Markovian decoherence dynamics of a dissipative two-level system, i.e., the so-called spin-boson model. It is interesting to find that the decoherence tends to be inhibited with the increase of the coupling…

Quantum Physics · Physics 2013-06-04 Hai-Bin Liu , Jun-Hong An , Chong Chen , Qing-Jun Tong , Hong-Gang Luo , C. H. Oh

A simplified Heisenberg spin model is studied in order to examine the idea of decoherence in closed quantum systems. For this purpose, we present a quantifiable definition to quantum coherence $\Xi$, and discuss in some detail a general…

Quantum Physics · Physics 2008-05-18 Olavi Dannenberg