Electronic Structures and Magnetic Phase Stability of L1_0 and B2-Type MnRh Equiatomic Alloys(Condensed matter : electronic structure and electrical, magnetic, and optical properties)

概要

論文の詳細を見る
We present magnetic properties, electronic structures and phase stability of L1_0- and B2-type MnRh equiatomic alloys. The calculated density of states for the L1_0-type equiatomic alloy in the collinear antiferromagnetic state exhibits a marked dip around the Fermi energy E_F. The experimental electronic specific heat coefficient γ_e of the L1_0-type equiatomic alloy is comparatively low of about 5.0 mJ mol^<-1> K^<-2>, verifying the theoretical calculation. The effective exchange constant J_0 in the collinear antiferromagnetic state is given to be about 171.9meV, corresponding to T_N=1330K in the molecular field approximation scheme. The theoretical results predict that the antiferromagnetism of the B2-type equiatomic alloy is unstable, implying that the ground state is very weak ferromagnetic or non-magnetic. On the other hand, the total energy of the B2-type alloy in the paramagnetic state is lower than that of the L1_0-type alloy, being consistent with the experimental fact that a diffusionless transformation between the L1_0- and B2-type structures occurs below room temperature.
社団法人日本物理学会の論文
2007-10-15