论文标题
由于放松时间各向异性，l1 $ _0 $ fept的四倍的各向异性磁路率
Fourfold anisotropic magnetoresistance of L1$_0$ FePt due to relaxation time anisotropy
论文作者
论文摘要
实验测量表明，在L1 $ _0 $中，各向异性磁倍率（AMR）的角度依赖性在当前方向和磁化方向上有序的fept外生膜，是对相应依赖性的叠加，这是两倍和四倍的符号的相应依赖性。双重AMR对当前方向表现出很强的依赖性，而四倍项仅取决于晶体中的磁化方向，并且独立于当前方向。第一原理的计算表明，由于磁化强度旋转的费米能量附近的状态密度的变化，弛豫时间各向异性产生。这种放松时间各向异性是铁磁金属中的通用特性，并确定了实验中可观察到的其他各向异性物理特性。
Experimental measurements show that the angular dependence of the anisotropic magnetoresistance (AMR) in L1$_0$ ordered FePt epitaxial films on the current orientation and magnetization direction is a superposition of the corresponding dependences of twofold and fourfold symmetries. The twofold AMR exhibits a strong dependence on the current orientation, whereas the fourfold term only depends on the magnetization direction in the crystal and is independent of the current orientation. First-principles calculations reveal that the fourfold AMR arises from the relaxation time anisotropy due to the variation of the density of states near the Fermi energy under rotation of the magnetization. This relaxation time anisotropy is a universal property in ferromagnetic metals and determines other anisotropic physical properties that are observable in experiment.
