Observation of van Hove Singularities in Twisted Silicene Multilayers.
Interlayer interactions perturb the electronic structure of two-dimensional materials and lead to new physical phenomena, such as van Hove singularities and Hofstadter's butterfly pattern. Silicene, the recently discovered two-dimensional form of silicon, is quite unique, in that silicon atoms adopt competing sp(2) and sp(3) hybridization states leading to a low-buckled structure promising relatively strong interlayer interaction. In multilayer silicene, the stacking order provides an important yet rarely explored degree of freedom for tuning its electronic structures through manipulating interlayer coupling. Here, we report the emergence of van Hove singularities in the multilayer silicene created by an interlayer rotation. We demonstrate that even a large-angle rotation (>20°) between stacked silicene layers can generate a Moiré pattern and van Hove singularities due to the strong interlayer coupling in multilayer silicene. Our study suggests an intriguing method for expanding the tunability of the electronic structure for electronic applications in this two-dimensional material.
Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong , Wollongong, New South Wales 2525, Australia.
Zhi
Z
Li
Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong , Wollongong, New South Wales 2525, Australia.
Jincheng
J
Zhuang
Institute of Physics, Chinese Academy of Sciences , Haidian District, Beijing 100080, China.
Lan
L
Chen
State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, China.
Zhenyi
Z
Ni
Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
Chen
C
Liu
Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong , Wollongong, New South Wales 2525, Australia.
Li
L
Wang
Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong , Wollongong, New South Wales 2525, Australia.
Xun
X
Xu
Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, People's Republic of China.
Jiaou
J
Wang
State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, China.
Xiaodong
X
Pi
Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong , Wollongong, New South Wales 2525, Australia.
Xiaolin
X
Wang
Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong , Wollongong, New South Wales 2525, Australia.
Yi
Y
Du
Institute of Physics, Chinese Academy of Sciences , Haidian District, Beijing 100080, China.
Kehui
K
Wu
Institute for Superconducting and Electronic Materials (ISEM), Australian Institute for Innovative Materials (AIIM), University of Wollongong , Wollongong, New South Wales 2525, Australia.
Shi Xue
SX
Dou