Design of self-organized nanostructures to achieve high blocking temperatures in MgO-based d (0) ferromagnets

作者：Seike Masayoshi^*; Fukushima Tetsuya; Sato Kazunori; Katayama Yoshida Hiroshi

来源：Journal of the Korean Physical Society, 2013, 62(12): 1807-1811.

DOI：10.3938/jkps.62.1807

• Self-organization
• Superparamagnetism
• d(0) ferromagnetism
• First-principles calculation
• Monte Carlo simulation
• Magnesium oxide

We present a materials design of MgO-based d (0) ferromagnets with a high blocking temperature (T (B) ) based on multiscale simulations. The chemical pair interactions between the N atoms in Mg(O,N) and the Mg vacancies (V-Mg) in (Mg,V-Mg)O were calculated using a generalized gradient approximation, and Monte Carlo simulations of the crystal growth were performed to predict the configurations of the dopant distribution. Our simulations showed that self-organized nanostructures could be formed both in Mg(O,N) and (Mg,V-Mg)O, which suggests that a high T (B) can be obtained in these d (0) ferromagnets due to the superparamagnetic blocking phenomenon. Furthermore, depending on the crystal growth conditions, it was shown that various self-organized nanostructures, such as three-dimensional nanoclusters and one-dimensional nanowires, could appear.

• 出版日期2013-7