Theory of thermally driven spin-transport in spin-orbit coupled systems

我们提出了一个协调的研究方案，研究由温度梯度驱动的自旋相关输运(准粒子自旋和电荷流)和磁激发(磁子)及其相关的非平衡声子。我们的重点将放在混合系统(包括磁性和非磁性组件)和具有自旋-轨道耦合的异质结构器件(隧道器件)上。我们将在理论上结合单粒子效应、集体效应和相对论效应来建立对横向自旋Seebeck效应物理的更好的微观理解；ii)探索新的各向异性磁热输运现象的可能性，例如各向异性隧道磁Seebeck效应；以及III)研究无序、非弹性过程和大的热梯度效应(探索线性响应的极限)对在包括室温在内的大范围温度下响应温度梯度而产生的横向(类霍尔型)自旋电流和磁矩的相互作用。为了充分阐明这些物理学并建立自信的预测能力，我们将利用和结合多种互补的理论方法和方法，其中一些是与SPP中的其他团队合作的。

We propose a coordinated research program on the study of spin-dependent transport (quasi-particle spin and charge currents) and magnetic excitations (magnons) driven by thermal gradients and their associated non-equilibrium phonons. Our focus will be on hybrid systems (containing magnetic and non-magnetic components) and hetero-structure devices (tunneling devices) with spin-orbit coupling. We will combine theoretically single-particle, collective, and relativistic effects to i) establish a better microscopic understanding of the physics of transverse spin Seebeck effect; ii) explore the possibility of novel anisotropic magneto-thermal transport phenomena such as Anisotropic Tunneling Magneto-Seebeck effect; and iii) study the interaction of disorder, inelastic processes, and large thermal gradient effects (exploring the limits of linear response) on the transverse (Hall like) spin-currents and magnetic torques generated in response to thermal gradients at a large range of temperatures, including room temperature. To fully elucidate these physics and build confident predictive power, we will utilize and combine multiple complementary theory methodologies and approaches, some in collaboration with other teams in the SPP.