Quantization of the band at the surface of charge density wave material 2H-TaSe2

• 作者: Man Li Nan Xu Jianfeng Zhang Rui Lou Ming Shi Lijun Li Hechang Lei Cedomir Petrovic Zhonghao Liu Kai Liu Yaobo Huang Shancai Wang
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: RAPID COMMUNICATION
• 页码范围: 117-124
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/1674-1056/abe9a8

摘要

By using angle-resolved photoemission spectroscopy(ARPES)combined with the first-principles electronic structure calculations,we report the quantized states at the surface of a single crystal 2H-TaSe2.We have observed sub-bands of quantized states at the three-dimensional Brillouin zone center due to a highly dispersive band with light effective mass along kz direction.The quantized sub-bands shift upward towards EF while the bulk band at Γ shifts downward with the decrease of temperature across charge density wave(CDW)formation.The band shifts could be intimately related to the CDW.While neither the two-dimensional Fermi-surface nesting nor purely strong electron-phonon coupling can explain the mechanism of CDW in 2H-TaSe2,our experiment may ignite the interest in understanding the CDW mechanism in this family.