摘要
Hall effects have been the central paradigms in modern physics,materials science and practical applications,and have led to many exciting breakthroughs,including the discovery of topological Chern invariants and the revolution of metrological resistance standard.To date,the Hall effects have mainly focused on a single degree of freedom(Do F),and most of them require the breaking of spatial-inversion and/or time-reversal symmetries.Here we demonstrate a new type of Hall effect,i.e.,layer-valley Hall effect,based on a combined layer-valley Do F characterized by the product of layer and valley indices.The layer-valley Hall effect has a quantum origin arising from the layer-valley contrasting Berry curvature,and can occur in nonmagnetic centrosymmetric crystals with both spatial-inversion and time-reversal symmetries,transcending the symmetry constraints of single Do F Hall effect based on the constituent layer or valley index.Moreover,the layer-valley Hall effect is highly tunable and shows a W-shaped pattern in response to the out-of-plane electric fields.Additionally,we discuss the potential detection approaches and material-specific design principles of layer-valley Hall effect.Our results demonstrate novel Hall physics and open up exotic paradigms for new research direction of layer-valleytronics that exploits the quantum nature of the coupled layer-valley DoF.
作者
赵交交
刘贵斌
陈鹏
姚裕贵
张广宇
杜罗军
Jiaojiao Zhao;Gui-Bin Liu;Peng Chen;Yugui Yao;Guangyu Zhang;Luojun Du(Beijing National Laboratory for Condensed Matter Physics,and Key Laboratory for Nanoscale Physics and Devices,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100190,China;Centre for Quantum Physics,Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE),School of Physics,Beijing Institute of Technology,Beijing 100081,China;Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic Systems,School of Physics,Beijing Institute of Technology,Beijing 100081,China;Schoolof Microelectronics,Southern University of Science and Technology,Shenzhen 518055,China;Songshan Lake Materials Laboratory,Dongguan 523808,China)
基金
supported by the National Natural Science Foundation of China(Grant Nos.61888102 and 12274447)
the National Key Research and Development Program of China(Grant Nos.2021YFA1202900 and 2023YFA1407000)
the KeyArea Research and Development Program of Guangdong Province,China(Grant No.2020B0101340001)
the Guangdong Major Project of Basic and Applied Basic Research(Grant No.2021B0301030002)
the Strategic Priority Research Program of Chinese Academy of Sciences(CAS)(Grant No.XDB0470101)。