Specific heat measurements were used to study the magnetic phase transition in Ga1-xMnxAs. Two different types of Ga1-xMnxAs samples have been investigated. The sample with a Mn concentration of 1.6% shows insulating behavior, and the sample with a Mn concentration of 2.6% is metallic. The temperature dependence of the specific heat for both samples reveals a pronounced lambda-shaped peak near the Curie temperature, which indicates a second-order phase transition in these samples. The critical behavior of the specific heat for Ga1-xMnxAs samples is consistent with the mean-field behavior with Gaussian fluctuations of the magnetization in the close vicinity of TC.
@article{arxiv.1006.1023,
title = {Specific heat study of Ga1-xMnxAs},
author = {Sh. U. Yuldashev and Kh. T. Igamberdiev and Sejoon Lee and Y. H. Kwon and T. W. Kang and Yongmin Kim and Hyunsik Im and A. G. Shashkov},
journal= {arXiv preprint arXiv:1006.1023},
year = {2015}
}