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Related papers: Disorder effects in diluted ferromagnetic semicond…

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We investigate ferromagnetism in the periodic Anderson model with diagonal disorder. Using dynamical mean-field theory in combination with the modified perturbation theory, the disorder can be included in the calculation consistently, which…

Strongly Correlated Electrons · Physics 2009-11-07 D. Meyer

We complete our earlier (Phys. Rev. B, {\bf 66}, 134435 (2002)) study of the electronic structure, exchange interactions and Curie temperature in (GaMn)As and extend the study to two other diluted magnetic semiconductors (GaCr)As and…

Materials Science · Physics 2009-11-10 L. M. Sandratskii , P. Bruno

We develop a lattice mean field theory for ferromagnetic ordering in diluted magnetic semiconductors by taking into account the spatial fluctuations associated with random disorder in the magnetic impurity locations and the finite mean free…

Materials Science · Physics 2009-11-10 D. J. Priour , E. H. Hwang , S. Das Sarma

We present a theory to model carrier mediated ferromagnetism in concentrated or diluted local moment systems. The electronic subsystem of the Kondo lattice model is described by a combined equation of motion / coherent potential…

Strongly Correlated Electrons · Physics 2011-04-22 M. Stier , W. Nolting

In this work we investigate Ising and classical Heisenberg models for two and three dimensional lattices in presence of diluted ferromagnetic dimers. For such models the Curie temperature as a function of ratio of intra-dimer exchange…

Strongly Correlated Electrons · Physics 2010-08-20 M. V. Medvedev , I. A. Nekrasov

We calculate magnetic couplings in the $J_{pd}$ model for dilute magnets, in order both to identify the relevant parameters which control ferromagnetism and also to bridge the gap between first principle calculations and model approaches.…

Strongly Correlated Electrons · Physics 2016-08-31 Richard Bouzerar , Georges Bouzerar , Timothy Ziman

It is predicted that III-V diluted magnetic semiconductors can exhibit stripe-like modulations of magnetization and carrier concentration. This inhomogeneity results from the strong dependence of the magnetization on the carrier…

Materials Science · Physics 2007-05-23 Carsten Timm

Considering a general situation where a semiconductor is doped by magnetic impurities leading to a carrier-induced ferromagnetic exchange coupling between the impurity moments, we show theoretically the possible generic existence of three…

Materials Science · Physics 2011-11-09 M. J. Calderon , S. Das Sarma

A (II,Mn)VI diluted magnetic semiconductor quantum dot with an integer number of electrons controlled with a gate voltage is considered. We show that a single conduction band electron is able to induce a spontaneous collective magnetization…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 J. Fernández-Rossier , L. Brey

We argue, in contrast to recent studies, that the antiferromagnetic superexchange coupling between nearest neighbour spins does not fully destroy the ferromagnetism in dilute magnets with long-ranged ferromagnetic couplings. Above a…

Disordered Systems and Neural Networks · Physics 2009-11-13 Georges Bouzerar , Richard Bouzerar , Olivier Cepas

Using a recently developed semi-analytical method (Self-Consistent Local RPA or SC-LRPA) we study the stability of the ferromagnetic phase in diluted magnetic systems where the exchange coupling between magnetic impurities are of RKKY form.…

Disordered Systems and Neural Networks · Physics 2009-11-11 Georges ~Bouzerar , Richard Bouzerar , Josef ~Kudrnovský , Timothy Ziman

We present a study of the dielectric function of metallic (III,Mn)V diluted magnetic semiconductors in the infrared regime. Our theoretical approach is based on the kinetic exchange model for carrier induced (III,Mn)V ferromagnetism. The…

Materials Science · Physics 2009-11-10 R. Aguado , M. P. López-Sancho , Jairo Sinova , L. brey

A review is given of advances in the field of carrier-controlled ferromagnetism in Mn-based diluted magnetic semiconductors and their nanostructures. Experimental results for III-V materials, where the Mn atoms introduce both spins and…

Materials Science · Physics 2015-06-24 Tomasz Dietl

We show theoretically that the magnetic ions, randomly distributed in a two-dimensional (2D) semiconductor system, can generate a ferromagnetic long-range order via the RKKY interaction. The main physical reason is the discrete (rather than…

Materials Science · Physics 2021-09-22 V. A. Stephanovich , E. V. Kirichenko , G. Engel , Yu. G. Semenov , K. W. Kim

The continual model of the nonuniform magnetism in thin films and wires of a diluted magnetic semiconductor is considered with taking into account the finite spin polarization of carriers responsible for the indirect interaction of magnetic…

Materials Science · Physics 2015-05-13 E. Z. Meilikhov , R. M. Farzetdinova

For modeling the magnetic properties of concentrated and diluted magnetic semiconductors, we use the Kondo-lattice model. The magnetic phase diagram is derived by inspecting the static susceptibility of itinerant band electrons, which are…

Materials Science · Physics 2009-11-10 W. Nolting , T. Hickel , A. Ramakanth , G. G. Reddy , M. Lipowczan

We propose a model of carrier-mediated ferromagnetism in semiconductors that accounts for the temperature dependence of the carriers. The model permits analysis of the thermodynamic stability of competing magnetic states, opening the door…

Materials Science · Physics 2010-11-09 A. G. Petukhov , Igor Zutic , Steven C. Erwin

A lattice spin-fermion model for diluted magnetic semiconductors (DMS) is investigated numerically, improving on previously used mean-field (MF) approximations. Curie temperatures are obtained varying the Mn-spin x and hole n densities, and…

Strongly Correlated Electrons · Physics 2009-11-07 Gonzalo Alvarez , Matthias Mayr , Elbio Dagotto

A mean field model of ferromagnetism mediated by delocalized or weakly localized holes in zinc-blende and wurzite diluted magnetic semiconductors is presented. The model takes into account: (i) strong spin-orbit and kp couplings in the…

Materials Science · Physics 2009-10-31 T. Dietl , H. Ohno , F. Matsukura

The doping of semiconductors with magnetic impurities gives rise not only to a spin-spin interaction between quasi-free carriers and magnetic impurities, but also to a local spin-independent disorder potential for the carriers. Based on a…

Mesoscale and Nanoscale Physics · Physics 2017-01-18 Moritz Cygorek , Florian Ungar , Pablo Ignacio Tamborenea , Vollrath Martin Axt