• 文献标题:   Charge Density Wave Vortex Lattice Observed in Graphene-Passivated 1T-TaS2 by Ambient Scanning Tunneling Microscopy
  • 文献类型:   Article
  • 作  者:   ALTVATER MA, TILAK N, RAO S, LI GH, WON CJ, CHEONG SW, ANDREI EY
  • 作者关键词:   stm, cdw, graphene, 1ttas2, oxidation, topological order, bragg glas
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:  
  • 被引频次:   7
  • DOI:   10.1021/acs.nanolett.1c01655 EA JUL 2021
  • 出版年:   2021

▎ 摘  要

The nearly commensurate charge density wave (CDW) excitations native to the transition-metal dichalcogenide crystal, 1T-TaS2, under ambient conditions are revealed by scanning tunneling microscopy (STM) and spectroscopy (STS) measurements of a graphene/TaS2 heterostructure. Surface potential measurements show that the graphene passivation layer prevents oxidation of the air-sensitive 1T-TaS2 surface. The graphene protective layer does not however interfere with probing the native electronic properties of 1T-TaS2 by STM/STS, which revealed that nearly commensurate CDW hosts an array of vortexlike topological defects. We find that these topological defects organize themselves to form a lattice with quasi-long-range order, analogous to the vortex Bragg glass in type-II superconductors but accessible in ambient conditions.