论文标题
无保守量的保守电流
Conserved current of nonconserved quantities
论文作者
论文摘要
我们为未经保守数量的保守电流提供了统一的半经典理论，并在两个物理环境中表现出来：Bloch电子的自旋电流和平均田bogoliubov Quasiparticles的电流电流。解决了限制电子旋转电流的操场的几个长期问题。我们透露，迄今忽略的扭矩四极密度和对扭矩偶极子密度的浆果相校正对于确保在平衡时消失的净流动流量消失的循环旋转电流至关重要。确定散装自旋传输的带状几何起源是动量空间自旋纹理和浆果曲率，而不是自旋浆果曲率，为材料相关研究铺平了道路。在超导体中，所达到的保守电荷电流对应于通过冷凝物回流重新归一化的准粒子电荷电流。它在平衡时的循环产生了轨道磁化，涉及超导性的特征，例如由非常规配对引起的浆果曲率和由移动的quasiparticles的电荷偶极子引起的轨道磁矩。
We provide a unified semiclassical theory for the conserved current of nonconserved quantities, and manifest it in two physical contexts: the spin current of Bloch electrons and the charge current of mean-field Bogoliubov quasiparticles. Several longstanding problems that limit the playground of the conserved spin current of electrons are solved. We reveal that the hitherto overlooked torque quadrupole density and Berry phase correction to the torque dipole density are essential to assure a circulating spin current with vanishing net flow at equilibrium. The band geometric origin of bulk spin transport is ascertained to be the momentum space spin texture and Berry curvature instead of the spin Berry curvature, paving the way for material related studies. In superconductors the attained conserved charge current corresponds to the quasiparticle charge current renormalized by the condensate backflow. Its circulation at equilibrium gives an orbital magnetization, which involves the characteristics of superconductivity, such as the Berry curvature arising from unconventional pairing and an orbital magnetic moment induced by the charge dipole of moving quasiparticles.
