论文标题
作为准颗粒的天空：自由能和熵
Skyrmions as quasiparticles: free energy and entropy
论文作者
论文摘要
根据Anomistic Spin Model模拟，在PD（111）上计算了（PT $ _ {0.95} $ ir $ _ {0.05} $ _ {0.05} $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir $ _ {0.95} $ ir。从非常低的温度开始进行模拟，直到天空数量的范围一直是由热波动不断创造和破坏的范围，突出了它们的准粒子性质。在低温下，较高的天空熵导致自由能的减少，因此，由于线性自旋波理论预测的熵稳定，由于熵稳定，天空在能量上优先于界线。超越线性自旋波近似，显示出符号变化在自由能以及高温下的熵中发生。
The free energy and the entropy of magnetic skyrmions with respect to the collinear state are calculated for a (Pt$_{0.95}$Ir$_{0.05}$)/Fe bilayer on Pd(111) via atomistic spin model simulations. The simulations are carried out starting from very low temperatures where the skyrmion number is conserved up to the range where skyrmions are constantly created and destroyed by thermal fluctuations, highlighting their quasiparticle nature. The higher entropy of the skyrmions at low temperature leads to a reduced free energy, such that the skyrmions become energetically preferred over the collinear state due to entropic stabilization as predicted by linear spin-wave theory. Going beyond the linear spin-wave approximation, a sign change is shown to occur in the free energy as well as the entropy at elevated temperature.
