Physics Letters A ( IF 2.6 ) Pub Date : 2020-12-22 , DOI: 10.1016/j.physleta.2020.127110 Jianhua Gong , Rui Zhu
By considering the topological Hall conductivity and the nanoribbon edge states, i.e., the bulk-boundary correspondence of the skyrmion crystal (SkX), this work focused on the relation of the topological properties to the next-nearest-neighbor (nnn) hopping (), the exchange coupling strength (J), and the topological number of the skyrmion (). When the nnn hopping of the electrons coexists with the nearest-neighbor hopping, the flux pattern of the emergent magnetic field traversing the SkX is reshaped giving rise to different topological Hall effect. By increasing from 0 to t, we found the Chern numbers of the electronic bands change from unity to indefinite values demonstrating a phase transition. By continually increasing from 1 to 2, we found topological phase transitions occur at and 1.7. We also considered the effect of finite J and found the results obtained in the adiabatic limit () hold to around .
中文翻译:
Skyrmion晶体中的拓扑数变化和下一近邻跳变驱动的拓扑相变
通过考虑拓扑霍尔电导率和纳米带边缘状态,即天体离子晶体(SkX)的体-边界对应关系,这项工作着眼于拓扑特性与下一近邻(nnn)跳跃之间的关系(),交换耦合强度(J)和天蝎子的拓扑数()。当电子的nnn跳变与最近邻的跳变并存时,穿过SkX的出射磁场的通量模式将被重塑,从而产生不同的拓扑霍尔效应。通过增加从0到t,我们发现电子带的Chern数从1变为不确定的值,表明发生了相变。通过不断增加 从1到2,我们发现拓扑相变发生在 和1.7。我们还考虑了有限J的影响,并发现在绝热极限()坚持 。