论文标题
具有两个矢量顺序参数的材料中各向异性磁化的理论
A theory for anisotropic magnetoresistance in materials with two vector order parameters
论文作者
论文摘要
各向异性磁阻（AMR）和相关的平面霍尔电阻（PHR）是磁性材料的普遍现象。尽管AMR和PHR在具有一个顺序参数的磁性多晶材料中的通用角依赖性是众所周知的，但迄今为止尚无类似的磁性材料的通用关系。在这里，我介绍了具有两个矢量顺序参数的磁性材料中的电磁效应的一般理论，例如具有主导的晶体轴的磁性单晶体或多晶非晶体非胶质性铁磁材料。结果表明，AMR和PHR具有通用的角度依赖性。通常，在没有反转对称性的情况下，纵向和横向电阻率都是非传向的：当电流逆转时，电阻率具有不同的值。与简单的磁性多晶材料不同，AMR和PHR具有相同的幅度，而$π/4 $偏置，具有两个矢量顺序参数的AMR和PHR的幅度通常不是相同的，并且相位差为$π/4 $。而不是通常的AMR和PHR的$π$周期性，带有两个订单参数的材料的周期性为$2π$。
Anisotropic magnetoresistance (AMR) and related planar Hall resistance (PHR) are ubiquitous phenomena of magnetic materials. Although the universal angular dependences of AMR and PHR in magnetic polycrystalline materials with one order parameter are well known, no similar universal relation for other class of magnetic materials are known to date. Here I present a general theory of galvanomagnetic effects in magnetic materials with two vector order parameters, such as magnetic single crystals with a dominated crystalline axis or polycrystalline non-collinear ferrimagnetic materials. It is shown that AMR and PHR have a universal angular dependence. In general, both longitudinal and transverse resistivity are non-reciprocal in the absence of inversion symmetry: Resistivity takes different value when the current is reversed. Different from simple magnetic polycrystalline materials where AMR and PHR have the same magnitude, and $π/4$ out of phase, the magnitude of AMR and PHR of materials with two vector order parameters are not the same in general, and the phase difference is not $π/4$. Instead of $π$ periodicity of the usual AMR and PHR, the periodicities of materials with two order parameters are $2π$.
