[14p-PA1-1~74] 10 Spintronics and Magnetics

▲ [14p-PA1-12] Strong enhancement of anomalous Nernst effect in Fe by Ga substitution and its application for heat flux sensor

〇Hiroyasu Nakayama¹, Keisuke Masuda¹, Weinan Zhou¹, Jian Wang¹, Asuka Miura¹, Ken-ichi Uchida^1,2,3, Masayuki Murata⁴, Yuya Sakuraba^1,5 (1.NIMS, 2.Tohoku Univ., 3.Univ. of Tokyo, 4.AIST, 5.JST PRESTO)

Keywords:anomalous Nernst effect

The anomalous Nernst effect (ANE) has been investigated in Fe_1-xGa_x alloy with different Ga atomic compositions in the range of x = 0-0.44. We fabricated Fe_1-xGa_x thin films on MgO(001) single-crystalline substrates by cosputtering technique. The systematic magnetotransport measurements and the first-principles calculations revealed that the large ANE in Fe_1-xGa_x is due to the large transverse Peltier coefficient. The maximum value of the theoretically calculated transverse Peltier coefficient shows good agreement with the experimentally determined values in Fe_1-xGa_x. The large enhancement of the ANE in Fe by replacing Fe atoms with Ga atoms can be mainly attributed to the shift of the Fermi energy, which can be understood as the electron doping effect. This kind of approach based on the Fermi energy engineering can be applicable to other magnetic materials. Therefore, these findings will provide crucial information to enhance the thermoelectric power through the ANE in various magnetic materials and pave the way to practical applications using ANE.