A research group led by Professor Shinobu Ohya and Professor Hikari Shinya of the Graduate School of Engineering has successfully elucidated the cause of the peculiar behavior of electrical conduction properties in the ferromagnetic semiconductor (Ga,Mn)As using new first principles calculations. The electrical conduction properties of (Ga,Mn)As have been a mystery for 30 years because of its metallic behavior at low temperatures and semiconducting behavior at high temperatures. In this study, they have developed a new first-principles calculation method that can predict the electrical conduction properties at finite temperatures, and have elucidated that spin fluctuation and atomic vibration effects are dominant at low and high temperatures, respectively. This will give momentum to the development of ferromagnetic semiconductor applications, and at the same time, the new first-principles calculation method developed this time can be applied to other material systems and is expected to contribute to the development of new materials. Researchers from the National Institute of Advanced Industrial Science and Technology (AIST) and Osaka University also participated in this joint research, and the resulting paper was published in the online edition of the scientific journal “APL Materials” on November 14.
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