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

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We discuss the operational definition of decoherence in various solid state systems. In particular, we review, in the context of spin-based solid state quantum computation, the introduction of $T_1$ and $T_2$ to describe decoherence in a…

Mesoscale and Nanoscale Physics · Physics 2017-08-23 Xuedong Hu , Rogerio de Sousa , S. Das Sarma

In this study, we investigate the decoherence of a spatially superposed electrically neutral spin-$\frac12$ particle in the presence of a relativistic quantum electromagnetic field in Minkowski spacetime. We demonstrate that decoherence due…

Quantum Physics · Physics 2024-10-30 Kensuke Gallock-Yoshimura , Yuuki Sugiyama , Akira Matsumura , Kazuhiro Yamamoto

Relaxation of a two-level system (TLS) into a resonant infinite-temperature reservoir with a Lorentzian spectrum is studied. The reservoir is described by a complex Gaussian-Markovian field coupled to the nondiagonal elements of the TLS…

Quantum Physics · Physics 2017-03-28 A. G. Kofman

Long-range quantum communication for spin qubits is an important open problem. Here we study decoherence of an electron spin qubit that is being transported in a moving quantum dot. We focus on spin decoherence due to spin-orbit interaction…

Mesoscale and Nanoscale Physics · Physics 2013-08-12 Peihao Huang , Xuedong Hu

We study decoherence of propagating spin-1/2 excitations in generic (non-integrable and/or disordered) spin chains. We find the relevant decoherence times to be shorter in both the near-critical and diffusive regimes (if any), which fact…

Strongly Correlated Electrons · Physics 2009-11-10 D. V. Khveshchenko

The simple stationary decoherence of a two-state quantum system is discussed from a new viewpoint of environmental entanglement. My work emphasizes that an unconditional local state must totally be disentangled from the rest of the…

Quantum Physics · Physics 2022-09-21 Lajos Diosi

We employ the method of the theory of open quantum systems to analyze spin relaxation and decoherence in semiconductors in the presence of a magnetic field. We derive a set of Bloch equations for electron spin with a fully microscopic…

Condensed Matter · Physics 2007-05-23 Vadim I. Puller , Lev G. Mourokh , Norman J. M. Horing , Anatoly Yu. Smirnov

This Letter studies the decoherence in a system of two antiferromagnetically coupled spins that interact with a spin bath environment. Systems are considered that range from the rotationally invariant to highly anisotropic spin models, have…

Quantum Physics · Physics 2007-05-23 S. Yuan , M. I. Katsnelson , H. De Raedt

A numerical procedure is presented for mapping the vicinity of the null-space of the spin relaxation superoperator. The states populating this space, i.e. those with near-zero eigenvalues, of which the two-spin singlet is a well-studied…

Chemical Physics · Physics 2014-07-16 H. J. Hogben , P. J. Hore , I. Kuprov

Numerical modelling of coherent spin relaxation in nanomagnets, formed by magnetic molecules of high spins, is accomplished. Such a coherent spin dynamics can be realized in the presence of a resonant electric circuit coupled to the magnet.…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 V. I. Yukalov , V. K. Henner , P. V. Kharebov

We consider a system of two spin-1/2 particles, initially in an entangled Bell state. If one of the particles is interacting with an environment (e.g. a collection of N independent spins), the two-particle system undergoes decoherence.…

Quantum Physics · Physics 2009-12-27 Fedor Levkovich-Maslyuk

We investigate the spin relaxation and spin dephasing of $n$-type GaAs quantum wells. We obtain the spin relaxation time $T_1$, the spin dephasing time $T_2$ and the ensemble spin dephasing time $T_2^{\ast}$ by solving the full microscopic…

Materials Science · Physics 2007-05-23 C. Lü , J. L. Cheng , M. W. Wu , I. C. da Cunha Lima

Exactly solvable models provide an opportunity to study different aspects of reduced quantum dynamics in detail. We consider the reduced dynamics of a single spin in finite XX and XY spin 1/2 chains. First we introduce a general expression…

Quantum Physics · Physics 2015-03-17 Oleg Lychkovskiy

The opportunity to build quantum technologies operating with elementary quantum systems with more than two levels is now increasingly being examined, not least because of the availability of such systems in the laboratory. It is therefore…

Quantum Physics · Physics 2022-03-07 Jérôme Denis , John Martin

We present an approach to spin dynamics by extending the optical Bloch equations for the driven two-level system to derive microscopic expressions for the transverse and longitudinal spin relaxation times. This is done for the 6-level…

Other Condensed Matter · Physics 2009-11-10 C. Lechner , U. Roessler

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

We find an exact solution for the problem of electron spin relaxation in a 2D circle with Rashba spin-orbit interaction. Our analysis shows that the spin relaxation in finite-size regions involves three stages and is described by multiple…

Mesoscale and Nanoscale Physics · Physics 2011-09-29 V. A. Slipko , Y. V. Pershin

Spin relaxation in a strong-coupling regime (with respect to the spin system) is investigated in detail based on the spin-boson model in a stochastic limit. We find a bifurcation phenomenon in temperature dependence of relaxation constants,…

Quantum Physics · Physics 2009-11-07 Gen Kimura , Kazuya Yuasa , Kentaro Imafuku

We study decoherence processes of an S = 1/2 localized spin coupled to conduction band electrons in a metal or a semiconductor via an Ising-like interaction. We derive master equations for the density matrix of the localized spin, by…

Materials Science · Physics 2009-11-13 Naoyoshi Yamada , Akimasa Sakuma , Hiroki Tsuchiura

We consider two mechanisms of spin relaxation in disordered graphene. i) Spin relaxation due to curvature spin orbit coupling caused by ripples. ii) Spin relaxation due to the interaction of the electronic spin with localized magnetic…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Daniel Huertas-Hernando , Francisco Guinea , Arne Brataas