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Related papers: Quantum Model Of Spin Noise

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We propose a mechanism to describe how a physical quantity, which initially can take continuous values, is restricted within some discrete values after a measurement. As an example of the present theory, in which interplay between coherence…

Quantum Physics · Physics 2007-05-23 Masato Morifuji

We measure and analyze noise-induced energy-fluctuations of spin qubits defined in quantum dots made of isotopically natural silicon. Combining Ramsey, time-correlation of single-shot measurements, and CPMG experiments, we cover the qubit…

Spin coherent states play a crucial role in defining QESM (quasi-exactly solvable models) establishing a strict correspondence between energy spectra of spin systems and low-lying quantum states for a particle moving in a potential field of…

Quantum Physics · Physics 2007-05-23 V. V. Ulyanov , O. B. Zaslavskii

Information spreads in time. For example, correlations dissipate when the correlated system locally couples to a third party, such as the environment. This simple but important fact forms the known quantum data-processing inequality. Here…

Quantum Physics · Physics 2024-03-15 Kun Zhang , Jin Wang

We analyze the notion of quantum coherence in an interference experiment. We let the phase shifts fluctuate according to a given statistical distribution and introduce a decoherence parameter, defined in terms of a generalized visibility of…

Quantum Physics · Physics 2010-01-31 A. Mariano , P. Facchi , S. Pascazio

A study of the non-dissipative Brownian motion in vacuum is presented. The noise source associated to the stochastic process assumed in this work is vacuum fluctuations of some quantum field capable of interact with a massive particle. For…

Classical Physics · Physics 2007-05-23 J. M. A. Figueiredo

We address the characterization of classical fractional random noise via quantum probes. In particular, we focus on estimation and discrimination problems involving the fractal dimension of the trajectories of a system subject to fractional…

Quantum Physics · Physics 2015-06-18 Matteo G. A. Paris

Quantum coherence, the physical property underlying fundamental phenomena such as multi-particle interference and entanglement, has emerged as a valuable resource upon which exotic modern technologies are founded. In general, the most…

We review some connections between quantum information and statistical mechanics. We focus on three sets of results for classical spin models. First, we show that the partition function of all classical spin models (including models in…

Quantum Physics · Physics 2013-12-23 Gemma De las Cuevas

The quantum measurement problems are revisited from a new perspective. One of the main ideas of this work is that the basic entities of our world are various types of particles, elementary or composite. It follows that each elementary…

Quantum Physics · Physics 2022-09-07 Kenichi Konishi

In classical mechanics, a natural way to simplify a many-body problem is to ``replace'' some of the elements of the composite system with surrogate \textit{force fields}. In the realm of quantum mechanics, however, such a description is…

Quantum Physics · Physics 2021-08-06 Piotr Szańkowski

The shot noise of spin polarized electrons is shown to be generically dependent upon spin-flip processes. Such a situation represents perhaps the simplest instance where the two-particle character of current fluctuations out of equilibrium…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 A. Lamacraft

Current fluctuations can provide additional insight into quantum transport in mesoscopic systems. The present work is carried out for the fluctuation properties of transport through a pair of coupled quantum dots which are connected with…

Mesoscale and Nanoscale Physics · Physics 2009-09-02 JunYan Luo , Xin-Qi Li , YiJing Yan

We review here the recent success in quantum annealing, i.e., optimization of the cost or energy functions of complex systems utilizing quantum fluctuations. The concept is introduced in successive steps through the studies of mapping of…

Quantum Physics · Physics 2010-09-21 Arnab Das , Bikas K. Chakrabarti

A notion of quantum multipole (in particular, dipole) noise is considered. Quantum dipole noise is an analogue of quantum white noise but it acts in a Fock space with indefinite metric. Quantum {\it white} noise describes the leading term…

Mathematical Physics · Physics 2007-05-23 A. N. Pechen , I. V. Volovich

We study the transfer dynamics of non-classical fluctuations of light to the ground-state collective spin components of an atomic ensemble during a pulsed quantum memory sequence, and evaluate the relevant physical quantities to be measured…

Quantum Physics · Physics 2009-11-11 Aurelien Dantan , Jean Cviklinski , Michel Pinard , Philippe Grangier

We study the dynamics of dephasing in a quantum two-level system by modeling both 1/f and high-frequency noise by random telegraph processes. Our approach is based on a so-called spin-fluctuator model in which a noisy environment is modeled…

Quantum Physics · Physics 2014-12-01 Alexander I. Nesterov , Gennady P. Berman

We apply a recently developed quantum theory of spin transfer torque to study the effect of the quantum noise in spin transfer process on the magnetization switching in spin-torque-driven devices. The quantum noise induces considerable…

Mesoscale and Nanoscale Physics · Physics 2013-07-10 Yong Wang , Yan Zhou , Fu-Chun Zhang

Crackling noise arises when a system responds to changing external conditions through discrete, impulsive events spanning a broad range of sizes. A wide variety of physical systems exhibiting crackling noise have been studied, from…

Statistical Mechanics · Physics 2009-11-07 James P. Sethna , Karin A. Dahmen , Christopher R. Myers

The expectation that it should not be possible to gain experimental insight on the structure of space-time at Planckian distance scales has been recently challenged by several studies. With respect to space-time fluctuations, one of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Giovanni Amelino-Camelia