Affiliation:
1. School of Integrated Circuits and Electronics MIIT Key Laboratory for Low‐Dimensional Quantum Structure and Devices Beijing Institute of Technology Beijing 100081 China
2. Institute of Physics Chinese Academy of Sciences Beijing 100190 China
Abstract
AbstractCharge density wave (CDW) is a typical collective phenomenon, and the phase change is generally accompanied by electronic transition with potential device applications. For the continuous miniaturization of devices, it is important to investigate the size effect down to the nanoscale. In this work, single‐layer (SL) 1T‐NbSe2 islands provide an ideal research platform to investigate the size effect on CDW arrangement and electronic states. The CDW motifs (Star‐of‐David [SOD]) at the island border are along the edge, and those at the interior tend to arrange in a triangular lattice for islands as small as 5 nm. Interestingly, in some small islands, the SOD clusters rearrange into a square‐like lattice, and each SOD cluster remains robust as a quantum motif, both in the sense of geometry and electronic structures. Moreover, the electronic structure at the center of the small islands is downwards shifted compared to the big islands, explained by the spatial extension of the band bending originating from the edge of the islands. These findings reveal the robust behavior of CDW motifs down to the nanoscale and provide new insights into the size‐limiting effect on 2D2D CDW ordering and electronic states down to a few nanometer extremes.
Funder
National Natural Science Foundation of China
National Key Research and Development Program of China
Natural Science Foundation of Beijing Municipality
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry