Manipulating valley-dependent Berry phase effects provides remarkable opportunities for both fundamental research and practical applications.Here,by referring to effective model analysis,we propose a general scheme fo...Manipulating valley-dependent Berry phase effects provides remarkable opportunities for both fundamental research and practical applications.Here,by referring to effective model analysis,we propose a general scheme for realizing topological magneto-valley phase transitions.More importantly,by using valley-half-semiconducting VSi2N4 as an outstanding example,we investigate sign change of valley-dependent Berry phase effects which drive the change-in-sign valley anomalous transport characteristics via external means such as biaxial strain,electric field,and correlation effects.As a result,this gives rise to quantized versions of valley anomalous transport phenomena.Our findings not only uncover a general framework to control valley degree of freedom,but also motivate further research in the direction of multifunctional quantum devices in valleytronics and spintronics.展开更多
基金This work is supported by the National Key R&D Program of China(Grant No.2020YFA0308800)the National Natural Science Foundation of China(Grant Nos.11734003,11874085,12047512,and 12004028)+4 种基金the Project Funded by China Postdoctoral Science Foundation(Grant Nos.2020M680011 and 2021T140057)Y.M.acknowledges the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)TRR 288-422213477(project B06)Y.M.,W.F.,and Y.Y.acknowledge the funding under the Joint Sino-German Research Projects(Chinese Grant No.12061131002&German Grant No.1731/10-1)the Sino-German Mobility Programme(Grant No.M-0142).
文摘Manipulating valley-dependent Berry phase effects provides remarkable opportunities for both fundamental research and practical applications.Here,by referring to effective model analysis,we propose a general scheme for realizing topological magneto-valley phase transitions.More importantly,by using valley-half-semiconducting VSi2N4 as an outstanding example,we investigate sign change of valley-dependent Berry phase effects which drive the change-in-sign valley anomalous transport characteristics via external means such as biaxial strain,electric field,and correlation effects.As a result,this gives rise to quantized versions of valley anomalous transport phenomena.Our findings not only uncover a general framework to control valley degree of freedom,but also motivate further research in the direction of multifunctional quantum devices in valleytronics and spintronics.
