Weißenhofer Markus, Rózsa Levente, Nowak Ulrich
Fachbereich Physik, Universität Konstanz, DE-78457 Konstanz, Germany.
Phys Rev Lett. 2021 Jul 23;127(4):047203. doi: 10.1103/PhysRevLett.127.047203.
Magnetic textures are often treated as quasiparticles following Thiele's equation of motion. We demonstrate via spin model simulations of the current-driven and Brownian motion of ferromagnetic skyrmions that the existing theory based on Thiele's equation is insufficient to describe the dynamics of skyrmions at finite temperatures. We propose an extended equation of motion that goes beyond Thiele's equation by taking into account the coupling of the skyrmion to the magnonic heat bath leading to an additional dissipative term that is linear in temperature. Our results indicate that this so-far-neglected magnon-induced friction dominates for finite temperatures and Gilbert damping values typical for thin films and multilayers.
磁纹理通常被视为遵循蒂勒运动方程的准粒子。我们通过对铁磁斯格明子的电流驱动和布朗运动进行自旋模型模拟表明，基于蒂勒方程的现有理论不足以描述有限温度下斯格明子的动力学。我们提出了一个扩展的运动方程，该方程超越了蒂勒方程，考虑了斯格明子与磁振子热库的耦合，从而产生了一个与温度成线性关系的附加耗散项。我们的结果表明，对于薄膜和多层膜典型的有限温度和吉尔伯特阻尼值，这种迄今被忽视的磁振子诱导摩擦起主导作用。
