Study of Ga<SUB>1-x</SUB>Mn<SUB>x</SUB>As Critical Behavior by Using Thermal Diffusivity

다국어 초록 (Multilingual Abstract)

The temperature dependence of the thermal diffusivity has been measured in the close vicinity of the magnetic phase transition in Ga_(1−x)Mn_xAs. The thermal diffusivity of Ga_(1−x)Mn_xAs samples demonstrated a pronounced -shaped peak, which indicates the existence of a second-order phase transition in the samples. The thermal diffusivity peak maximum is located near the Curie temperature;therefore, it is attributed to a ferromagnetic-paramagnetic phase transition. Taking into account that the inverse of the thermal diffusivity has the same critical behavior as the specific heat,we determine the critical exponent . The critical behavior of the specific heat of the Ga_(1−x)Mn_xAs samples is well described by the mean-field, including Gaussian fluctuations, model.

참고문헌 (Reference)

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