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Numerical study of spin-fermion models for diluted magnetic semiconductors and high Tc cuprates [electronic resource] /

by Yildirim, Yu?cel

Abstract (Summary)
ABSTRACT: In this dissertation, Spin-Fermion (SF) models for diluted magnetic semiconductors and high temperature superconducting cuprates are constructed and studied with unbiased numerical techniques. A microscopic model to describe magnetically doped III-V semiconductors is proposed. This model includes the appropriate lattice geometry, as well as, magnetic, spin-orbit, and Coulomb interactions and contains no free parameters. Its study using state-of-the-art numerical techniques provides results in excellent agreement with experimental data for $Mn$ doped GaAs. For the first time, Curie-Weiss behavior of the magnetization is obtained numerically and the values of the Curie temperature are reproduced in a wide range of $Mn$ doping and compensations. We observed that for $xge 3\%$, the holes are doped into the valence band and uniformly distributed in the material. This could support the ``valence band' scenario regarding this material.
Bibliographical Information:

Advisor:

School:Florida State University

School Location:USA - Florida

Source Type:Master's Thesis

Keywords:diluted magnetic semiconductors dms multi band model realistic lattice spin fermion models high temperature cuprates

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