发表机构
Universidade Federal do Espírito Santo; University of Manitoba（圣埃斯皮里图联邦大学; 曼尼托巴大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过数值模拟揭示偶极斯格明子链在淬火无序中的集体脱钉行为，发现阈值与链长无关且为孤立斯格明子的三分之一，并阐明热与非热圆化机制，对链式信息载体器件有指导意义。
AI 中文摘要
通过随机Thiele方程的数值解，研究了弱钉扎势垒中相互作用的偶极斯格明子链的动力学。在不同磁场下，具有周期性边界条件的不同长度的链被驱动穿过淬火吸引钉扎位点。一个清晰的阈值自旋电流被确定为临界脱钉力。主要结果有三：（i）对于50个或更多斯格明子的链，脱钉阈值与链长无关，并保持接近孤立斯格明子阈值的三分之一。（ii）转变圆化仅是部分热性的：宽度从T=0时的w=0.334±0.004个数量级变化到300 K时的0.633±0.002，而内在的Larkin关联长度在kBT~V0/25以下保持约2.6个键。（iii）宽度在kBT~0.14 V0以下几乎不变，但在kBT~0.23 V0时增加近四倍，主要通过蠕变区域的拓宽实现。它与链长无关，排除了有限尺寸圆化。将磁场从30 mT增加到40 mT会改变转变形状，使其核心加宽26%，同时缩短蠕变尾部。对于约200个斯格明子的链，脱钉通过一系列内部变形进行——Larkin长度和粗糙度的增长、瞬态键拉伸，以及随后迁移率和霍尔角的恢复。这些集体效应对于基于斯格明子的器件具有重要意义，在这些器件中，链而非孤立纹理作为信息载体。
英文摘要
The dynamics of interacting dipole skyrmion chains in a weak pinning landscape is studied through numerical solutions of the stochastic Thiele equation. Chains of different lengths with periodic boundary conditions are driven across quenched attractive pinning sites under different magnetic fields. A clear threshold spin current is identified as the critical depinning force. Three main results emerge: (i) for chains of 50 skyrmions or more, the depinning threshold is independent of chain length and remains close to one third of that of an isolated skyrmion. (ii) The transition rounding is only partly thermal: the width changes from w = 0.334 +/- 0.004 decades at T = 0 to 0.633 +/- 0.002 at 300 K, while the intrinsic Larkin correlation length remains about 2.6 bonds below kBT ~ V0/25. (iii) The width is nearly unchanged up to kBT ~ 0.14 V0, but increases almost fourfold by kBT ~ 0.23 V0, mainly through broadening of the creep regime. It is independent of chain length, ruling out finite-size rounding. Increasing the field from 30 to 40 mT changes the transition shape, widening its core by 26% while shortening the creep tails. For chains of about 200 skyrmions, depinning proceeds through a sequence of internal deformations - growth of the Larkin length and roughness, transient bond stretching, and subsequent recovery of mobility and Hall angle. These collective effects are relevant for skyrmion-based devices in which chains, rather than isolated textures, act as information carriers.
