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Related papers: Flux noise in disordered spin systems

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Although the Fluctuation-Dissipation framework is a first step to get a quantum model for electrical noise, the merging of displacement and conduction currents into the sole current of a series notion like the resistance R(f) does not help…

Mesoscale and Nanoscale Physics · Physics 2017-09-21 J. I. Izpura

We present a quantum field theoretic formulation of acoustoelectric interactions in waveguide-like systems of arbitrary cross-section. Building on an open quantum systems approach, we derive a unified description of plasmon-phonon coupling…

Recent experiments by F. Yoshihara et al. [Phys. Rev. Lett. 97, 167001 (2006)] and by K. Kakuyanagi et al. (cond-mat/0609564) provided information on decoherence of the echo signal in Josephson-junction flux qubits at various bias…

Superconductivity · Physics 2009-11-11 Y. M. Galperin , B. L. Altshuler , J. Bergli , D. Shantsev , V. Vinokur

An effective spin relaxation mechanism that leads to electron spin decoherence in a quantum dot is proposed. In contrast to the common calculations of spin-flip transitions between the Kramers doublets, we take into account a process of…

Materials Science · Physics 2009-11-10 Y. G. Semenov , K. W. Kim

We present a new method to measure 1/f noise in Josephson quantum bits (qubits) that yields low-frequency spectra below 1Hz. Comparison of noise taken at positive and negative bias of a phase qubit shows the dominant noise source to be flux…

Antiferromagnets are promising candidates as active components in spintronic applications. They share features with ferrimagnets in that opposing spin orientations exist in two or more sublattices. Spin transfer torque and spin pumping are…

Mesoscale and Nanoscale Physics · Physics 2024-09-24 Hans Gløckner Giil , Arne Brataas

In s-wave superconductors with a small concentration of magnetic impurities, the only electronic excitations that remain available at low temperatures are the excitations of the system of localized spins. We discuss a new mechanism of…

Superconductivity · Physics 2025-12-12 Shiang-Bin Chiu , Anton Andreev , Alexander Burin , Boris Z. Spivak

Bosons with non-zero spin exhibit a rich variety of superfluid and insulating phases. Most phases support coherent spin oscillations, which have been the focus of numerous recent experiments. These spin oscillations are Rabi oscillations…

Strongly Correlated Electrons · Physics 2009-04-05 Stephen Powell , Subir Sachdev

We contribute an extension of large-deviation results obtained in [N.J.B. Aza, J.-B. Bru, W. de Siqueira Pedra, A. Ratsimanetrimanana, J. Math. Pures Appl. 125 (2019) 209] on conductivity theory at atomic scale of free lattice fermions in…

Mathematical Physics · Physics 2021-03-03 J. -B. Bru , W. de Siqueira Pedra , A. Ratsimanetrimanana

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

Noise and decoherence due to spurious two-level systems (TLS) located at material interfaces is a long-standing issue in solid state quantum technologies. Efforts to mitigate the effects of TLS have been hampered by a lack of surface…

The interplay of electronic interactions and frustration in crystalline systems leads to a panoply of correlated phases, including exotic Mott insulators with non-trivial patterns of entanglement. Disorder introduces additional quantum…

Strongly Correlated Electrons · Physics 2025-01-03 Sunghoon Kim , Mohammad Saad , Dan Mao , Adhip Agarwala , Debanjan Chowdhury

We consider finite frequency noise in a mesoscopic system with arbitrary interactions, connected to many terminals kept at finite electrochemical potentials. We show that the excess noise, obtained by subtracting the noise at zero voltage…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Ines Safi

Current-voltage measurements of type-II superconductors are described by a coarse-grained model of superconducting vortex dynamics. We find that the power spectra of the voltage fluctuations, and the noise power, are related to the large…

Statistical Mechanics · Physics 2007-05-23 Kevin E. Bassler , Joern Davidsen , Maya Paczuski

This paper presents a theoretical description of the spin distributions of fragments from low-energy induced and spontaneous nuclear fission, expressed in an analytical form. The mechanism of pumping high spin values for deformed fission…

Electron spin qubits are a promising platform for quantum computation. Environmental noise impedes coherent operations by limiting the qubit relaxation ($T_1$) and dephasing ($T_{\phi}$) times. There are multiple sources of such noise,…

Quantum Physics · Physics 2022-09-27 Yujun Choi , Robert Joynt

Spin fluctuations have a substantial influence on the electron and lattice behaviors in magnetic materials, which, however, is difficult to be tracked properly by prevalent first-principles methods. We propose a versatile self-adaptive…

Materials Science · Physics 2023-02-14 Zefeng Cai , Ke Wang , Yong Xu , Su-Huai Wei , Ben Xu

Non-equilibrium excess noise of a short quasi one-dimensional constriction between two superconductors is considered. A general expression for the current-current correlation function valid for arbitrary temperatures and bias voltages is…

Condensed Matter · Physics 2009-10-28 J. P. Hessling , V. S. Shumeiko , Yu. M. Galperin , G. Wendin

Using a microfluidics device filled with a colloidal suspension of microspheres, we test the laws of diffusion in the limit of small particle numbers. Our focus is not just on average properties such as the mean flux, but rather on the…

Statistical Mechanics · Physics 2007-05-23 Effrosyni Seitaridou , Mandar M. Inamdar , Rob Phillips , Kingshuk Ghosh , Ken Dill

We study the isothermal Brownian dynamics of a particle in a system with spatially varying diffusivity. Due to the heterogeneity of the system, the particle's mean displacement does not vanish even if it does not experience any physical…

Statistical Mechanics · Physics 2017-11-22 Oded Farago