Eur. Phys. J. B 81, 405-409 (2011)
https://doi.org/10.1140/epjb/e2011-20320-x

Magnetic spin excitations in Mn doped GaAs: a model study

¹ Institut Néel, CNRS, Département MCBT, 25 avenue des Martyrs, B.P. 166, 38042 Grenoble Cedex 09, France
² School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany

Corresponding author: ^a akash.chakraborty@grenoble.cnrs.fr

Received: 4 February 2011
Revised: 26 April 2011
Published online: 21 June 2011

Abstract

We provide a quantitative theoretical model study of the dynamical magnetic properties of optimally annealed Ga_1-xMn_xAs. This model has already been shown to reproduce accurately the Curie temperatures for Ga_1-xMn_xAs. Here we show that the calculated spin stiffness are in excellent agreement with those which were obtained from ab-initio based studies. In addition, an overall good agreement is also found with available experimental data. We have also evaluated the magnon density of states and the typical density of states from which the “mobility edge”, separating the extended from localized magnon states, was determined. The power of the model lies in its ability to be generalized for a broad class of diluted magnetic semiconductor materials, thus it bridges the gap between first principle calculations and model based studies.