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Related papers: Spin-polarons in an exchange model

200 papers

We present numerically exact inchworm quantum Monte Carlo results for the real-time dynamics of the spin polarization in the sub-Ohmic spin-boson model at finite temperature. We focus in particular on the localization and coherence behavior…

Strongly Correlated Electrons · Physics 2026-03-31 Olga Goulko , Hsing-Ta Chen , Moshe Goldstein , Guy Cohen

We present the results of muon-spin relaxation measurements of spin excitations in the one-dimensional quantum Heisenberg antiferromagnet Cu(pyz)(NO$_{3}$)$_{2}$. Using density-functional theory we propose muon sites and assess the degree…

Strongly Correlated Electrons · Physics 2015-05-20 F. Xiao , J. S. Möller , T. Lancaster , R. C. Williams , F. L. Pratt , S. J. Blundell , D. Ceresoli , A. M. Barton , J. L. Manson

We have found the mechanism of the electron Cooper pair formation via the electron interaction by means of the spin-electron acoustic waves. This mechanism takes place in metals with rather high spin polarization, like ferromagnetic,…

Superconductivity · Physics 2015-10-14 Pavel A. Andreev , P. A. Polyakov , L. S. Kuz'menkov

Spin-polarized scanning tunneling microscopy investigations reveal a significant increase of the magnetic period of spin spirals in three-atomic-layer-thick Fe films on Ir(111), from about 4nm at 8K to about 65nm at room temperature. We…

Mesoscale and Nanoscale Physics · Physics 2017-07-26 Aurore Finco , Levente Rózsa , Pin-Jui Hsu , André Kubetzka , Elena Vedmedenko , Kirsten von Bergmann , Roland Wiesendanger

The behavior of the compensation temperature of a mixed Ising ferrimagnetic system on a square lattice in which the two interpenetrating square sublattices have spins $\sigma$ ($\pm 1/2$) and spins $S$ ($\pm 1,0$) has been studied with…

Materials Science · Physics 2007-05-23 G. M. Buendia , E. Machado , M. A. Novotny

Thermodynamics of a spin-1 Bose gas with ferromagnetic interactions are investigated via the mean-field theory. It is apparently shown in the specific heat curve that the system undergoes two phase transitions, the ferromagnetic transition…

Statistical Mechanics · Physics 2009-11-13 Chengjun Tao , Peilin Wang , Jihong Qin , Qiang Gu

We apply the classical mapping technique developed recently by Dharma-wardana and Perrot for a study of the uniform two-dimensional electron system at arbitrary degeneracy and spin-polarization. Pair distribution functions, structure…

Strongly Correlated Electrons · Physics 2009-11-10 Nguyen Quoc Khanh , Hiroo Totsuji

The physics of strongly correlated fermions described by Hubbard or $t$-$J$ models in the underdoped regime -- relevant for high-temperature superconductivity in cuprate compounds -- remains a subject of ongoing debate. In particular, the…

Strongly Correlated Electrons · Physics 2025-04-11 Toni Guthardt , Markus Scheb , Jan von Delft , Annabelle Bohrdt , Fabian Grusdt

A spin-fermion model that captures the charge-transfer properties of Cu-based high critical temperature superconductors is introduced and studied via Monte Carlo simulations. The strong Coulomb repulsion among $d$-electrons in the Cu…

Strongly Correlated Electrons · Physics 2018-07-25 Mostafa Sherif Derbala Aly Hussein , Maria Daghofer , Elbio Dagotto , Adriana Moreo

We analyze the phase transition between spin-singlet and spin-polarized states which occurs at $\nu=2/3$. The basic strategy is to use adiabatic flux-trading arguments to relate this transition to the analogous transition at $\nu=2$. The…

Condensed Matter · Physics 2009-10-28 Chetan Nayak , Frank Wilczek

We have studied the magnetic and transport properties of an ultra-low-resistivity two-dimensional electron system in a Si/SiGe quantum well. The spin polarization increases linearly with the in-plane magnetic field and the enhancement of…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Tohru Okamoto , Mitsuaki Ooya , Kunio Hosoya , Shinji Kawaji

In spin crossover materials, an abrupt phase transition between a low spin state and a high spin state can be driven by temperature, pressure or by light irradiation. Of a special relevance are Fe(II) based coordination polymers where, in…

The temperature dependence of the static magnetic susceptibility of exchange-disordered antiferromagnetic Heisenberg spin-1/2 finite chains with an odd number of spins is investigated as a function of size and type of disorder in the…

Strongly Correlated Electrons · Physics 2009-01-29 C. M. Chaves , Thereza Paiva , J. d'Albuquerque e Castro , Belita Koiller

Interaction effects are dramatically enhanced in flat-band systems due to quenched kinetics, facilitating the binding of single excitations into composite quasiparticles. In this work, we present a comprehensive study of spin polarons over…

Strongly Correlated Electrons · Physics 2026-02-11 Wei-Tao Zhou , Zhao-Yang Dong , Jian-Xin Li

In conventional spin glasses, magnetic interaction is not strongly anisotropic and the entire spin system is believed to be frozen below the spin-glass transition temperature. In La2Cu0.94Li0.06O4, for which the in-plane exchange…

Superconductivity · Physics 2007-05-23 Y. Chen , Wei Bao , Y. Qiu , J. E. Lorenzo , J. L. Sarrao , D. L. Ho , Min Y. Lin

A `toy model' - aimed at capturing the essential physics - is presented that jointly describes spin-polarized hot electron transport and spin pumping driven by local heating. These two processes both contribute to spin-current generation in…

Mesoscale and Nanoscale Physics · Physics 2022-12-21 Maarten Beens , Koen de Mare , Rembert Duine , Bert Koopmans

We consider a mixture of spin-1/2 bosons and fermions, where only the bosons are subjected to the spin-orbit coupling induced by Raman beams. The fermions, although not directly coupled to the Raman lasers, acquire an effective spin-orbit…

Atomic Physics · Physics 2019-09-25 Chuanzhou Zhu , Li Chen , Hui Hu , Xia-Ji Liu , Han Pu

We study the motion of free magnetic polarons in a paramagnetic background of fluctuating local moments. The polaron can tunnel only to nearby regions of local moments when these fluctuate into alignment. We propose this fluctuation induced…

Strongly Correlated Electrons · Physics 2009-11-07 L. G. L. Wegener , P. B. Littlewood

Raman scattering studies as functions of temperature, magnetic field, and Gd-substitution are used to investigate the evolution of magnetic polarons and spin-carrier interactions through the metal-insulator transition in…

Strongly Correlated Electrons · Physics 2009-11-07 H. Rho , C. S. Snow , S. L. Cooper , Z. Fisk , A. Comment , J-Ph Ansermet

A theory accounting for the specific features of magnetic polarons (MP) in the presence of spin glass order is presented. We derive and solve selfconsistent equations for i) the polaron magnetisation, ii) the thermodynamically averaged…

Disordered Systems and Neural Networks · Physics 2009-10-30 A. L. Chudnovskiy , R. Oppermann , B. Rosenow , D. R. Yakovlev , U. Zehnder , W. Ossau