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arXiv · 1006.1023

Specific heat study of Ga1-xMnxAs

Sh. U. Yuldashev·Kh. T. Igamberdiev·Sejoon Lee·Y. H. Kwon·T. W. Kang·Yongmin Kim·Hyunsik Im·A. G. Shashkov
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Abstract

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.

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Sh. U. Yuldashev, Kh. T. Igamberdiev, Sejoon Lee, Y. H. Kwon, T. W. Kang, Yongmin Kim, Hyunsik Im, A. G. Shashkov. 2010-06-05. Specific heat study of Ga1-xMnxAs. https://doi.org/10.1143/apex.3.073005

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