Signatures of strong interlayer coupling in γ-InSe revealed by local differential conductivity

• 作者: Xiaoshuai Fu Li Liu Li Zhang Qilong Wu Yu Xia Lijie Zhang Yuan Tian Long-Jing Yin Zhihui Qin
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: RAPID COMMUNICATION
• 页码范围: 182-188
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-1056/abff32

摘要

Interlayer coupling in layered semiconductors can significantly affect their optoelectronic properties.However,un-derstanding the mechanisms behind the interlayer coupling at the atomic level is not straightforward.Here,we study modulations of the electronic structure induced by the interlayer coupling in the γ-phase of indium selenide (γ-InSe) us-ing scanning probe techniques.We observe a strong dependence of the energy gap on the sample thickness and a small effective mass along the stacking direction,which are attributed to strong interlayer coupling.In addition,the moiré pat-tems observed in γ-InSe display a small band-gap variation and nearly constant local differential conductivity along the patterns.This suggests that modulation of the electronic structure induced by the moiré potential is smeared out,indicating the presence of a significant interlayer coupling.Our theoretical calculations confirm that the interlayer coupling in γ-InSe is not only of the van der Waals origin,but also exhibits some degree of hybridization between the layers.Strong interlayer coupling might play an important role in the performance of γ-InSe-based devices.