Related papers: Effective Heisenberg exchange integrals of diluted…
The magnetic properties of the diluted magnetic semiconductors (DMS) (Ga, Mn)As and (Ga, Mn)N are investigated by means of an effective Heisenberg model, whose exchange parameters are obtained from first-principle calculations. The…
A microscopic Hamiltonian for interacting manganese impurities in diluted magnetic semiconductors (DMS) is derived. It is shown that in p -type III-V DMS the indirect exchange between Mn impurities has similarities with the Zener mechanism…
We investigate the interaction of two Mn ions in the dilute magnetic semiconductor GaMnAs using the variational envelope wave function approach within the framework of six band model of the valence band. We find that the effective…
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…
A theory of the electronic response in spin and charge disordered media is developed with the particular aim to describe III-V dilute magnetic semiconductors like GaMnAs. The theory combines a detailed k.p description of the valence band,…
A recently discovered magnetic semiconductor Ba$_{1-x}$K$_{x}$(Zn$_{1-y}$Mn$_{y}$)$_2$As$_{2}$, with its decoupled spin and charge doping, provides a unique opportunity to elucidate the microscopic origin of the magnetic interaction and…
A microscopic model of indirect exchange interaction between transition metal impurities in dilute magnetic semiconductors (DMS) is proposed. The hybridization of the impurity d-electrons with the heavy hole band states is largely…
We investigate the role of exchange bridges in molecular magnets. We explore their effects on the distribution of the valence electrons and their contribution to the exchange processes. The present study is focused on a spin-half dimer with…
We consider the extended Hubbard model and introduce a corresponding Heisenberg-like problem written in terms of spin operators. The derived formalism is reminiscent of Anderson's idea of the effective exchange interaction and takes into…
We propose a new mechanism of indirect exchange interaction, which can be responsible for the ferromagnetic ordering in Mn-doped semiconductors (like GaMnAs) at low carrier concentration. The mechanism is based on the interplay of the…
The influence of substitutional disorder on the magnetic properties of diluted Heisenberg spin systems is studied with regard to the magnetic stability of ferromagnetic diluted semiconductors (DMS). The equation of motion for the magnon…
Applying the dynamical coherent potential approximation to a simple model, we have theoretically studied the behavior of the optical bandedge in diluted magnetic semiconductors (DMSs). For $A^{\rm II}_{1-x}$Mn$_{x}B^{\rm VI}$-type DMS, the…
Starting from microscopic and symmetry considerations, we derive the Hamiltonian describing the exchange interaction between the localized Mn spins and the valence band holes in $Ga_{1-x}Mn_x As$. We find that due to the strong spin-orbit…
We have performed ab initio calculations within the density-functional theory for Ga_{1-x}Mn_xAs diluted semiconductors. Total energy results unambiguously show that a quasi-localized down-spin hole, with strong p-like character, surrounds…
In this report we review the method of explicit calculations of interatomic exchange interactions of magnetic materials. This involves exchange mechanisms normally referred to as Heisenberg exchange, Dzyaloshinskii-Moriya interaction and…
One of the remarkable properties of the II-VI diluted magnetic semiconductor (ZnMn)Se is the giant spin splitting of the valence band states under application of the magnetic field (giant Zeeman splitting). This splitting reveals strong…
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,…
Diluted magnetic semiconductors (DMS) are interesting because of the interplay between the electronic and magnetic subsystems. We describe selected magnetic properties of IV-VI diluted magnetic semiconductors, looking at the similarities…
The magnetic properties of dilute magnetic semiconductors (DMS) are calculated from first-principles by mapping the ab initio results on a classical Heisenberg model. It is found that the range of the exchange interaction in (Ga, Mn)N is…
Motivated by the recent suggestion of anisotropic effective exchange interactions between Mn spins in Ga$_{1-x}$Mn$_x$As (arising as a result of spin-orbit coupling), we study their effects in diluted Heisenberg spin systems. We perform…