论文标题
磁性八杆作为非常规抗铁磁性的顺序参数
Magnetic octupoles as the order parameter for unconventional antiferromagnetism
论文作者
论文摘要
我们表明，具有非层次性自旋分解的时间反向对称性破碎的中心对称性抗铁磁体，可方便地用磁性八杆的铁序订购来方便地描述。在这种情况下，磁性八杆是最低的铁序磁量，因此自然顺序参数是过渡到磁有序状态的。它们提供了统一的描述，描述了损坏的时间反转对称性和非忠实的自旋分裂以及处理后者的平台，并解释了其他现象，例如Piezomagnetism，这是这类抗Fiferromagnets的特征。对于抗铁磁铁而言，我们表明磁性八杆可以引起非零的磁性康普顿散射，为其直接实验检测提供了途径。我们使用密度功能和模型计算来说明这些概念，用于原型的非旋转式抗fiferromagnet，金红石结构锰difuoride，mnf2。
We show that time-reversal symmetry broken, centrosymmetric antiferromagnets with nonrelativistic spin-splitting are conveniently described in terms of the ferroic ordering of magnetic octupoles. The magnetic octupoles are the lowest-order ferroically ordered magnetic quantity in this case, and so are the natural order parameter for the transition into the magnetically ordered state. They provide a unified description of the broken time-reversal symmetry and the non-relativistic spin splitting as well as a platform for manipulating the latter, and account for other phenomena, such as piezomagnetism, characteristic of this class of antiferromagnets. Unusually for antiferromagnets, we show that the magnetic octupoles cause a non-zero magnetic Compton scattering, providing a route for their direct experimental detection. We illustrate these concepts using density-functional and model calculations for the prototypical non-relativistic spin-split antiferromagnet, rutile-structure manganese difuoride, MnF2.
