[25a-32A-1~10] 9.5 New functional materials and new phenomena

10:45 AM - 11:00 AM JST(1:45 AM - 2:00 AM UTC)

[25a-32A-7] Investigation on the electronic structures of magnetic shape memory alloy Ni₂Mn_1+xGa_1-x by quasiparticle self-consistent GW approach

〇Masao Obata¹, Takao Kotani², Tatsuki Oda¹ (1.Kanazawa Univ., 2.Tottori Univ.)

Keywords:

magnetic shape memory alloy,Ni-Mn-Ga alloy,GW method

Ni-Mn-Ga alloys possess both ferromagnetic and shape memory properties, expecting their functional material applications, such as high-speed magnetic field-induced actuators. Their crystal structure at low temperatures forms a modulated martensitic structure, which contains nano-twinning boundaries at the martensite phase. We performed electronic structure calculation of Ni₂Mn_1+xGa_1-x (x=0,0.25) utilizing the quasiparticle self-consistent GW (QSGW) approach. The QSGW result shows that the high-temperature phase has electronic instability to the modulated martensitic structure corresponding to experimental observation. The effect of non-stoichiometric composition on the electronic structure instability will also be discussed in the presentation.