English
Related papers

Related papers: Spin decoherence due to Fluctuating Fields

200 papers

Universal conductance fluctuations are usually observed in the form of aperiodic oscillations in the magnetoresistance of thin wires as a function of the magnetic field B. If such oscillations are completely random at scales exceeding…

Disordered Systems and Neural Networks · Physics 2020-06-24 V. V. Brazhkin , I. M. Suslov

Spin noise spectroscopy is a technique to measure magnetization fluctuations, a subject of increasing relevance in ultrafast spintronics. We investigate numerically the equilibrium spin noise of ferro- and antiferromagnets within an…

Materials Science · Physics 2024-11-28 Julius Schlegel , Martin Evers , Ulrich Nowak

The theory of spin fluctuations is developed for an ensemble of localized electrons taking into account both hyperfine interaction of electron and nuclear spins and electron hopping between the sites. The analytical expression for the spin…

Mesoscale and Nanoscale Physics · Physics 2015-05-07 M. M. Glazov

In the presence of spatial variation of the magnetization direction, electric current noise causes a fluctuating spin-transfer torque that increases the fluctuations of the ferromagnetic order parameter. By the fluctuation-dissipation…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Jorn Foros , Arne Brataas , Yaroslav Tserkovnyak , Gerrit E. W. Bauer

In this report, we examine the decoherence of a spin qubits system coupled to counted spin chain with a $1/r^2$ interaction by using influence functional. We also examine the time evolution of density matrix numerically when environment is…

Mesoscale and Nanoscale Physics · Physics 2008-12-20 Toshifumi Itakura

Quantum dot-based spin qubits are resilient towards charge noise and are affected by magnetic noise only. However, environmental interaction leads to decoherence in these qubit systems. The external control parameters are directly related…

Mesoscale and Nanoscale Physics · Physics 2022-01-19 Tanmay Sarkar , Yash Tiwari , Vishvendra Singh Poonia

Quantum decoherence can arise due to classical fluctuations in the parameters which define the dynamics of the system. In this case decoherence, and complementary noise, is manifest when data from repeated measurement trials are combined.…

General Relativity and Quantum Cosmology · Physics 2011-09-13 G. J. Milburn

The high temperature limit of interacting spins is usually not associated with ordering or critical phenomena. Nevertheless, spontaneous fluctuations of a local spin polarization at equilibrium have nontrivial dynamics even in this limit.…

Statistical Mechanics · Physics 2023-07-03 V. N. Gorshkov , N. A. Sinitsyn , D. Mozyrsky

A slanting magnetic field is usually used to realize a slight hybridization between the spin and orbital degrees of freedom in a semiconductor quantum dot, such that the spin is manipulable by an external oscillating electric field. Here we…

Mesoscale and Nanoscale Physics · Physics 2021-07-08 Rui Li

Any ensemble of quantum particles exhibits statistical fluctuations known as spin noise. Here, we provide a description of spin noise in the language of open quantum systems. The description unifies the signatures of spin noise under both…

Quantum Physics · Physics 2015-03-04 R. Annabestani , D. G. Cory , J. Emerson

Universal conductance fluctuations are usually observed in the form of aperiodic oscillations in the magnetoresistance of thin wires as a function of the magnetic field B. If such oscillations are completely random at scales exceeding…

Disordered Systems and Neural Networks · Physics 2021-12-28 I. M. Suslov

By Faraday-rotation fluctuation spectroscopy one measures the spin noise via Faraday-induced fluctuations of the polarization plane of a laser transmitting the sample. In the fist part of this paper, we present a theoretical model of recent…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Matthias Braun , Jürgen König

We analyze the frequency dependence of shot noise in a spin filter consisting of a normal grain and ferromagnetic electrodes separated by tunnel barriers. The source of frequency-dependent noise is random spin-flip electron scattering that…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 K. E. Nagaev , L. I. Glazman

The loss of coherence is one of the main obstacles for the implementation of quantum information processing. The efficiency of dynamical decoupling schemes, which have been introduced to address this problem, is limited itself by the…

The dependence of mesoscopic conductance fluctuations on parallel magnetic field is used as a probe of spin degeneracy in open GaAs quantum dots. The variance of fluctuations at high parallel field is reduced from the low-field variance…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 J. A. Folk , S. R. Patel , K. M. Birnbaum , C. M. Marcus , C. I. Duruoz , J. S. Harris

This paper identifies and investigates nature of the transition between Gaussian and exponential forms of decoherence. We show that the decoherence factor (that controls the time dependence of the suppression of the off-diagonal terms when…

Quantum Physics · Physics 2022-11-23 Bin Yan , Wojciech H. Zurek

The paper critically overviews the recent developments of the theory of spin fluctuations (SF) in itinerant electron magnetism with particular emphasis on spin-fluctuation coupling or spin anharmonicity. It is argued that the conventional…

Strongly Correlated Electrons · Physics 2015-12-09 A. Solontsov

Common philosophy in control theory is the control of disorder by order. It is not exceptional for strategies suppressing quantum decoherence. Here we predict an anomalous quantum phenomenon. Suppression of decoherence can be made via more…

Quantum Physics · Physics 2013-11-05 Jun Jing , Lian-Ao Wu

The electron spin relaxation process in n-type GaAs crystals driven by a fluctuating electric field is investigated. Two different sources of fluctuations are considered: (i) a symmetric dichotomous noise and (ii) a Gaussian correlated…

Mesoscale and Nanoscale Physics · Physics 2013-12-18 Stefano Spezia , Dominique Persano Adorno , Nicola Pizzolato , Bernardo Spagnolo

We summarize the present status of the theories of spin fluctuations in dealing with the anomalous or non-Fermi liquid behavior and unconventional superconductivity in strongly correlated electron systems around their magnetic instabilities…

Strongly Correlated Electrons · Physics 2007-05-23 Toru Moriya