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Related papers: Spin fluctuations in quantum dots

200 papers

We study the effective dynamics of ferromagnetic spin chains in presence of long-range interactions. We consider the Heisenberg Hamiltonian in one dimension for which the spins are coupled through power-law long-range exchange interactions…

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 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

Magnetic phase transitions between ordered phases are often understood on the basis of semi-classical spin models. Deviations from the classical description due to the quantum nature of the atomic spins as well as quantum fluctuations are…

Strongly Correlated Electrons · Physics 2026-05-19 Tobias Dannegger , Imre Hagymási , Levente Rózsa , Ulrich Nowak

We present a full fledged quantum mechanical treatment of the interplay between the charge and the spin zero-mode interactions in quantum dots. Quantum fluctuations of the spin-mode suppress the Coulomb blockade and give rise to…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. N. Kiselev , Yuval Gefen

The dynamical behaviour of the quantum state of different quantum spin chains, with designed site dependent interaction strengths, is analyzed when the initial state belongs to the one excitation subspace. It is shown that the inhomogeneous…

Quantum Physics · Physics 2022-10-26 Alejandro Ferrón , Pablo Serra , Omar Osenda

We investigate spin quantum-fluctuation effects that originate from the Heisenberg uncertainty principle during the dynamical cycle of disentanglement, entanglement, and re-disentanglement between itinerant electrons and localized magnetic…

Mesoscale and Nanoscale Physics · Physics 2026-03-24 Jie Zheng , Jiyong Kang , Zheng Zhu , Di Wu , Yuesheng Li , Dongxing Yu , Jiayong Wang , Hongxing Xu , Chenglong Jia

The universal quantum computation is obtained when there exists asymmetric anisotropic exchange between electron spins in coupled semiconductor quantum dots. The asymmetric Heisenberg model can be transformed into the isotropic model…

Quantum Physics · Physics 2009-11-13 Xiang Hao , Shiqun Zhu

Fluctuation of Coulomb blockade peak spacings in large two-dimensional semiconductor quantum dots are studied within a model based on the electrostatics of several electron islands among which there are random inductive and capacitive…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Yshai Avishai , Daniel Berend , Richard Berkovits

Inelastic spin relaxation and spin splitting $\epsilon_{\mathrm{s}}$ in lateral quantum dots are studied in the regime of strong in-plane magnetic field. Due to both g-factor energy dependence and spin-orbit coupling $\epsilon_{\mathrm{s}}$…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Vladimir I. Fal'ko , B. L. Altshuler , O. Tsyplyatev

We study the dependency of the quantum spin dynamics on the particle number in a system of ultracold spin-1 atoms within the single-spatial-mode approximation. We find, for all strengths of the spin-dependent interaction, convergence…

Quantum Gases · Physics 2010-09-02 Jannes Heinze , Frank Deuretzbacher , Daniela Pfannkuche

We analyze the stability of spin spiral states in the two-dimensional Heisenberg model. Our analysis reveals that the SU(2) symmetric point hosts a dynamic instability that is enabled by the existence of energetically favorable transverse…

Statistical Mechanics · Physics 2022-07-07 Joaquin F. Rodriguez-Nieva , Alexander Schuckert , Dries Sels , Michael Knap , Eugene Demler

We review progress on the spintronics proposal for quantum computing where the quantum bits (qubits) are implemented with electron spins. We calculate the exchange interaction of coupled quantum dots and present experiments, where the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Hans-Andreas Engel , L. P. Kouwenhoven , Daniel Loss , C. M. Marcus

The dramatic growth of research areas within the province of quantum state transmission (QST) is rapidly accelerating. An important insight to understand the process of QST can be fulfilled by considering the dynamical behavior of its…

Quantum Physics · Physics 2021-02-24 Mostafa Motamedifar

Controlling electron spins in double quantum dots allows individual electrons to be trapped and manipulated for next-generation solid-state qubit devices. In this paper, the study analyzes spin relaxation due to deformation potentials of…

Mesoscale and Nanoscale Physics · Physics 2026-05-19 Sanjay Prabhakar

Research on the emergence of thermodynamics in closed quantum systems under unitary time evolution arrived at the consensus that generic systems equilibrate under rather general assumptions. A new focus of the field is thus on exceptions.…

Strongly Correlated Electrons · Physics 2025-02-19 J. Eckseler , J. Schnack

We review recent studies on spin decoherence of electrons and holes in quasi-two-dimensional quantum dots, as well as electron-spin relaxation in nanowire quantum dots. The spins of confined electrons and holes are considered major…

Mesoscale and Nanoscale Physics · Physics 2009-07-28 Jan Fischer , Mircea Trif , W. A. Coish , Daniel Loss

This study discusses the quantum behavior of a particle, which is controlled by fluctuations in the physical space-time (ST) variables, rather than provides a novel interpretation of quantum theory. The fluctuations, i.e., inhomogeneities…

General Physics · Physics 2012-06-15 Valery Egorushkin

This study investigates the entanglement properties of quantum dots (QDs) under a universal Hamiltonian where the Coulomb interaction between particles (electrons or holes) decouples into a charging energy and an exchange coupling term.…

Quantum Physics · Physics 2024-08-13 Jahanfar Abouie , Daryoosh Vashaee

Phenomenological approach is developed in the theory of spin-valve type ferromagnetic junctions to describe exchange switching by current flowing perpendicular to interfaces. Forward and backward current switching effects are described and…

Materials Science · Physics 2007-05-23 E. M. Epshtein , Yu. V. Gulyaev , P. E. Zilberman