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arXiv · 1703.06636

A Monte Carlo study of critical properties of strongly diluted magnetic semiconductor (Ga,Mn)As

P. Tomczak·H. T. Diep·P. Jabłoński·H. Puszkarski
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Abstract

Within a Monte Carlo technique we examine critical properties of diluted bulk magnetic semiconductor (Ga,Mn)As modeled by a strongly diluted ferromagnetic Heisenberg spin-$\frac{5}{2}$ system on a face centered cubic lattice. We assumed that 5\% of Ga atoms is substituted by Mn atoms and the interaction between them is of the RKKY-type. The considered system is randomly quenched and a double average was performed: firstly, over the Boltzmann probability distribution and secondly - over 2048 configurations related to the quenched disorder. We estimated the critical temperature: $T_c=97\pm6$ K, which is in agreement with the experiment. The calculated high value of critical exponent $\nu$ seems to point to a possibility of non-universal critical behavior.

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P. Tomczak, H. T. Diep, P. Jabłoński, H. Puszkarski. 2017-03-20. A Monte Carlo study of critical properties of strongly diluted magnetic semiconductor (Ga,Mn)As. https://doi.org/10.12693/aphyspola.133.514

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