English
Related papers

Related papers: Magnetic Exchange in Spin Clusters

200 papers

We study indirect exchange interactions between localized spins of magnetic impurities in spin-valley coupled systems described with the Kane-Mele model. Our model captures the main ingredients of the energy bands of 1H transition metal…

Mesoscale and Nanoscale Physics · Physics 2022-12-13 M. R. Losada , A. T. Costa , B. Biel , J. Fernández-Rossier

In this paper a microscopic theory of spin fluctuations in an ensemble of electrons localized on donors in a bulk semiconductor has been developed. Both the hyperfine interaction of the electron spin with spins of lattice nuclei and the…

Mesoscale and Nanoscale Physics · Physics 2015-06-16 D. S. Smirnov , M. M. Glazov , E. L. Ivchenko

We propose a method to determine the magnetic exchange interaction and on-site anisotropy tensors of extended Heisenberg spin models from density functional theory including relativistic effects. The method is based on the…

Using Path Integral Monte Carlo we have calculated exchange frequencies as electrons undergo ring exchanges in a ``clean'' 2d Wigner crystal as a function of density. The results show agreement with WKB calculations at very low density, but…

Strongly Correlated Electrons · Physics 2009-10-31 B. Bernu , Ladir Candido , D. M. Ceperley

We consider mechanism of exchange coupling based on interaction between electrons in nonmagnetic layer. Depending on ratio of inverse time of diffusion of electrons between ferromagnetic layers and ferromagnetic splitting of conducting…

Mesoscale and Nanoscale Physics · Physics 2009-09-29 Zyuzin A. Yu

We investigate the influence of an interband exchange interaction on magnetism in a two-band Hubbard model. Our main emphasis lies on spin-flip scattering which is often neglected but is neccessary to retain the full rotational symmetry of…

Strongly Correlated Electrons · Physics 2009-10-31 D. Meyer , W. Nolting

Schwinger bosons allow for an advantageous representation of quantum double-exchange. We review this subject, comment on previous results, and address the transition to the semiclassical limit. We derive an effective fermionic Hamiltonian…

Strongly Correlated Electrons · Physics 2007-05-23 A. Weisse , J. Loos , H. Fehske

We derive an effective spin Hamiltonian for the one-dimensional half-filled asymmetric ionic Hubbard model with alternating on-site interaction in the limit of strong repulsion. It is shown that the effective Hamiltonian is that of a spin…

Strongly Correlated Electrons · Physics 2016-02-01 Inna Grusha , Mikheil Menteshashvili , George I. Japaridze

We consider the spin-1/2 Heisenberg chain with alternating spin exchange %on even and odd sites in the presence of additional modulation of exchange on odd bonds with period three. We study the ground state magnetic phase diagram of this…

Strongly Correlated Electrons · Physics 2015-05-30 M. Shahri Naseri , G. I. Japaridze , S. Mahdavifar , S. Farjami Shayesteh

Current-induced switching is considered in a magnetic junction. The junction includes pinned and free ferromagnetic layers which work in the regime of the high spin injection. It is shown that in such a regime the exchange magnetization…

Materials Science · Physics 2015-05-13 S. G. Chigarev , E. M. Epshtein , P. E. Zilberman

In an effort to understand the low temperature behavior of recently synthesized molecular magnets we present numerical evidence for the existence of a rotational band in systems of quantum spins interacting with nearest-neighbor…

Materials Science · Physics 2009-10-31 J. Schnack , Marshall Luban

Electric fields are increasingly used for coherently manipulating spin states in semiconductor and molecular systems. Here we discuss the spin manipulation allowed by the modulation of the main parameters entering the Hamiltonians of…

Mesoscale and Nanoscale Physics · Physics 2019-11-05 F. Troiani

The effect of exchange interactions within spin pairs on spin-dependent transport and recombination rates through localized states in semiconductors during coherent electron spin resonant excitation is studied theoretically. It is shown…

Materials Science · Physics 2008-01-09 A. Gliesche , C. Michel , V. Rajevac , K. Lips , S. D. Baranovskii , F. Gebhard , C. Boehme

Using an ensemble of atoms in an optical cavity, we engineer a family of nonlocal Heisenberg Hamiltonians with continuously tunable anisotropy of the spin-spin couplings. We thus gain access to a rich phase diagram, including a…

The marked interplay between the crystalline, electronic, and magnetic structure of atomically thin magnets has been regarded as the key feature for designing next-generation magneto-optoelectronic devices. In this respect, a detailed…

Strongly Correlated Electrons · Physics 2020-05-25 Michele Pizzochero , Ravi Yadav , Oleg V. Yazyev

We study the spin-dependent magneto conductance in mesoscopic rings subject to an inhomogeneous in-plane magnetic field. We show that the polarization direction of transmitted spin-polarized electrons can be controlled via an additional…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Diego Frustaglia , Martina Hentschel , Klaus Richter

From general arguments, that are valid for spin models with sufficiently short-range interactions, we derive strong constraints on the excitation spectrum across a continuous phase transition at zero temperature between a magnetic and a…

Strongly Correlated Electrons · Physics 2009-11-11 Leonardo Spanu , Federico Becca , Sandro Sorella

The multiple-spin exchange frequencies of the bilayer Wigner crystal are determined by the semiclassical method, which is asymptotically exact in the limit of dilute electron densities. The evolution of the exchange frequencies with…

Strongly Correlated Electrons · Physics 2025-03-05 Ilya Esterlis , Dmitry Zverevich , Zekun Zhuang , Alex Levchenko

Conventional superexchange rules predict ferromagnetic exchange interaction between Ni(II) and M (M=Mo(V), W(V), Nb(IV)). Recent experiments show that in some systems this superexchange is antiferromagnetic. To understand this feature, in…

Strongly Correlated Electrons · Physics 2009-11-11 Rajamani Raghunathan , Jean-Pascal Sutter , Laurent Ducasse , Cedric Desplanches , S. Ramasesha

We studied the exchange interactions mediated by polarized itinerant carriers in diluted magnetic semiconductor (DMS) junction. In contrast to the ordinary RKKY oscillations, the induced moment possesses an interesting spiral motion,…

Other Condensed Matter · Physics 2009-11-10 Shih-Jye Sun , Song-Shien Cheng , Hsiu-Hau Lin