First principles calculation for the magnetic damping constants of transition metal alloys and magnetic multilayers

2015 Fiscal Year Final Research Report

• Project/Area Number: 25420686
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Physical properties of metals/Metal-base materials
• Research Institution: Tohoku University
• Principal Investigator: Sakuma Akimasa 東北大学, 工学(系)研究科(研究院), 教授 (30361124)
• Co-Investigator(Kenkyū-buntansha): MIURA Daisuke 東北大学, 大学院工学研究科, 助教 (90708455)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ギルバート緩和 / スピン動力学 / 第一原理計算 / 遷移金属 / ホイスラー合金

Outline of Final Research Achievements

We have theoretically studied the microscopic feature of the Gilbert damping in magnetization dynamics, and performed the first principles calculation for the Gilbert damping constant, α for transition metal alloys. We found that the two different descriptions for α by torque correlation (TC) method and spin correlation (SC) method in turn provide the same result and furthermore the TC method is more suitable for actual calculations for α, because it avoids some problems in numerical processes. Based on this consideration, using the first principles technique under the TC method, we have calculated αfor some Heusler alloys and clarified that the value of α is strongly affected by the density of states at the Fermi level.

Free Research Field

磁性物理