Topological kinetic crossover in a nanomagnet array
成果类型：
Article
署名作者：
Zhang, Xiaoyu; Fitez, Grant; Subzwari, Shayaan; Bingham, Nicholas S.; Chioar, Ioan-Augustin; Saglam, Hilal; Ramberger, Justin; Leighton, Chris; Nisoli, Cristiano; Schiffer, Peter
署名单位：
Yale University; United States Department of Energy (DOE); Los Alamos National Laboratory; University of Minnesota System; University of Minnesota Twin Cities; Yale University; University of Maine System; University of Maine Orono
刊物名称：
SCIENCE
ISSN/ISSBN：
0036-8841
DOI：
10.1126/science.add6575
发表日期：
2023-05-05
页码：
526-531
关键词：
摘要：
Ergodic kinetics, which are critical to equilibrium thermodynamics, can be constrained by a system's topology. We studied a model nanomagnetic array in which such constraints visibly affect the behavior of the magnetic moments. In this system, magnetic excitations connect into thermally active one-dimensional strings whose motion can be imaged in real time. At high temperatures, our data showed the merging, breaking, and reconnecting of strings, resulting in the system transitioning between topologically distinct configurations. Below a crossover temperature, the string motion is dominated by simple changes in length and shape. In this low-temperature regime, the system is energetically stable because of its inability to explore all possible topological configurations. This kinetic crossover suggests a generalizable conception of topologically broken ergodicity and limited equilibration.