Maegochi S, Ienaga K, Okuma S
Department of Physics, Tokyo Institute of Technology, 2-12-1 Ohokayama, Meguro-ku, Tokyo, 152-8551, Japan.
Sci Rep. 2024 Jan 12;14(1):1232. doi: 10.1038/s41598-024-51534-5.
Dynamical ordering from a disordered plastic flow to an anisotropically ordered smectic flow induced by a dc force has been studied in various many-particle systems, including vortices in type-II superconductors. However, it remains unclear whether the dynamical ordering is a true phase transition because of lack of suitable experimental methods. Here, we study the response of vortex flow to the transverse force using a cross-shaped amorphous Mo[Formula: see text]Ge[Formula: see text] film. From transverse current-voltage (force-velocity) characteristics under various longitudinal currents, we find a change of the transverse response in low voltage (velocity) regions from a nonlinear to linear behavior at a well-defined longitudinal current that marks the dynamical ordering transition. We also find the scaling collapse of the transverse current-voltage curves to a universal scaling function, providing evidence of the second-order transition for the dynamical ordering transition.
在包括II型超导体中的涡旋在内的各种多粒子系统中，已经研究了由直流力诱导的从无序塑性流到各向异性有序近晶流的动力学排序。然而，由于缺乏合适的实验方法，动力学排序是否是真正的相变仍不清楚。在这里，我们使用十字形非晶Mo[公式：见正文]Ge[公式：见正文]薄膜研究涡旋流对横向力的响应。从各种纵向电流下的横向电流-电压（力-速度）特性，我们发现在低电压（速度）区域，横向响应在一个明确的纵向电流处从非线性行为转变为线性行为，该纵向电流标志着动力学排序转变。我们还发现横向电流-电压曲线缩放到一个通用的标度函数，为动力学排序转变的二级相变提供了证据。
