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We observe asymmetric transition rates between Zeeman levels (spin-flips) of magnetically trapped atoms. The asymmetry strongly depends on the spectral shape of an applied noise. This effect follows from the interplay between the internal…

Quantum Physics · Physics 2010-11-12 S. Machluf , J. Coslovsky , P. G. Petrov , Y. Japha , R. Folman

The dynamics of a spin in the presence of a deterministic and a fluctuating magnetic field is solved for analytically to obtain the averaged value of the spin as a function of time for various kinds of fluctuations (noise). Specifically,…

Mesoscale and Nanoscale Physics · Physics 2014-03-21 Piotr Szańkowski , M. Trippenbach , Y. B. Band

We investigate non-equilibrium quantum spin systems via an exact mapping to stochastic differential equations. This description is invariant under a shift in the mean of the Gaussian noise. We show that one can extend the simulation time…

Strongly Correlated Electrons · Physics 2021-12-28 S. E. Begg , A. G. Green , M. J. Bhaseen

We consider a single spin in a constant magnetic field or an anisotropy field. We show that additional external time-periodic fields with zero mean may generate nonzero time-averaged spin components which are vanishing for the time-averaged…

Statistical Mechanics · Physics 2014-09-11 S. Flach , A. A. Ovchinnikov

We consider properties of a two-dimensional electron system in a random magnetic field. It is assumed that the magnetic field not only influences orbital electron motion but also acts on the electron spin. For calculations, we suggest a new…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Kazutaka Takahashi , K. B. Efetov

A dynamic mean-field theory for spin ensembles (spinDMFT) at infinite temperatures on arbitrary lattices is established. The approach is introduced for an isotropic Heisenberg model with $S = \tfrac12$ and external field. For large…

Statistical Mechanics · Physics 2022-02-03 Timo Gräßer , Philip Bleicker , Dag-Björn Hering , Mohsen Yarmohammadi , Götz S. Uhrig

We study, using Monte Carlo dynamics, the time ($t$) dependent average magnetization per spin $m(t)$ behavior of 2-D kinetic Ising model under a binary ($\pm h_0$) stochastic field $h(t)$. The time dependence of the stochastic field is such…

Statistical Mechanics · Physics 2013-12-02 Asim Ghosh , Bikas K. Chakrabarti

Spin dynamics in spatially inhomogeneous magnetic fields is studied within the framework of Boltzmann theory. Stern-Gerlach-like separation of spin up and spin down electrons occurs in ballistic and diffusive regimes, before spin relaxation…

Condensed Matter · Physics 2007-05-23 Jaroslav Fabian , S. Das Sarma

We consider Bayesian estimate of static magnetic field, characterized by a prior Gaussian probability distribution, in systems of a few electron quantum dot spins interacting with infinite temperature spin environment via hyperfine…

Quantum Physics · Physics 2016-11-15 Paweł Mazurek , Michał Horodecki , Łukasz Czekaj , Paweł Horodecki

We have theoretically studied the temporal fluctuations and the resulting kinetic noise in the average spin polarization of an electron ensemble drifting in a quantum wire under a high electric field. Electrons are initially injected in the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 S. Pramanik , S. Bandyopadhyay

Spin transitions are studied theoretically and experimentally in a resonantly excited system of cavity polaritons in a magnetic field. Weak pair interactions in this boson system make possible fast and massive spin flips occurring at…

Mesoscale and Nanoscale Physics · Physics 2015-06-12 S. S. Gavrilov , A. V. Sekretenko , N. A. Gippius , C. Schneider , S. Höfling , M. Kamp , A. Forchel , V. D. Kulakovskii

We consider random walk on a mildly random environment on finite transitive d- regular graphs of increasing girth. After scaling and centering, the analytic spectrum of the transition matrix converges in distribution to a Gaussian noise. An…

Probability · Mathematics 2011-11-10 Dimitrios Cheliotis , Balint Virag

It seems that a stochastic system must be a nonlinear one to observe the phenomenon, noise induced transition. But in the present paper, we have demonstrated that the phenomenon may be observed even in a linear stochastic process where both…

Statistical Mechanics · Physics 2022-01-04 Shrabani Mondal , L. R. Rahul Biswas , Mousumi Biswas , Bidhan Chandra Bag

Conductance fluctuations in GaAs quantum dots with spin-orbit and Zeeman coupling are investigated experimentally and compared to a random matrix theory formulation that defines a number of regimes of spin symmetry depending on experimental…

Mesoscale and Nanoscale Physics · Physics 2012-08-27 D. M. Zumbuhl , J. B. Miller , D. Goldhaber-Gordon , C. M. Marcus , J. S. Harris, , K. Campman , A. C. Gossard

We consider the hyperfine-mediated transition rate between Zeeman split spin states of the lowest orbital level in a GaAs quantum dot. We separate the hyperfine Hamiltonian into a part which is diagonal in the orbital states and another one…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Sigurdur I. Erlingsson , Yuli V. Nazarov

A method is presented to calculate the spin relaxation times T1, T2 due to a non-uniform magnetic field, and the linear-in-electric-field precession frequency shift {\delta}{\omega}E when an electric field is present, in the diffusion…

Atomic Physics · Physics 2015-05-20 Steven M. Clayton

We analyze the influence of classical Gaussian noise on Landau-Zener transitions during a two-level crossing in a time-dependent regular external field. Transition probabilities and coherence factors become random due to the noise. We…

Statistical Mechanics · Physics 2009-11-10 V. L. Pokrovsky , S. Scheidl

We consider the behavior of an Ising ferromagnet obeying the Glauber dynamics under the influence of a fast switching, random external field. After introducing a general formalism for describing such systems, we consider here the mean-field…

Statistical Mechanics · Physics 2009-10-31 J. Hausmann , P. Rujan

The Zeeman effect lowers the energy of electrons with spin states which are anti-parallel to the applied magnetic field but lifts that of spin parallel states. In quantum spin liquids where the spin and charge degrees of freedom are…

Strongly Correlated Electrons · Physics 2023-06-05 Wen-Yu He , Patrick A. Lee

The influence of a magnetic field on the broadening of spectral lines and transition arrays in complex spectra is investigated. The anomalous absorption or emission Zeeman pattern is a superposition of many profiles with different relative…

Atomic Physics · Physics 2019-04-30 Jean-Christophe Pain , Franck Gilleron
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