Nanoscale electronic inhomogeneities in 1T-TaS$_2$

B. Campbell; J. V. Riffle; A. de la Torre; Q. Wang; K. W. Plumb; S. M. Hollen

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arXiv · 2310.19751

Nanoscale electronic inhomogeneities in 1T-TaS$_2$

B. Campbell·J. V. Riffle·A. de la Torre·Q. Wang·K. W. Plumb·S. M. Hollen

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Abstract

We report a set of scanning tunneling microscopy (STM) and spectroscopy (STS) experiments studying native defects in CVT grown 1T-TaS$_2$. Six different sample surfaces from four bulk crystals were investigated. Wide area imaging reveals a prevalence of nanometer-scale electronic inhomogeneities due to native defects, with pristine regions interspersed. These inhomogeneities appear in typical as-grown crystals and coexist with a well-formed commensurate charge density wave of 1T-TaS$_2$ at low temperatures. Electronic inhomogeneities show up both as variations in the apparent height in STM and in the local density of states in STS; the bands can shift by 60 meV and the gap varies by more than 100 meV across inhomogeneities. These inhomogeneities are present in similar concentration across large-scale areas of all samples studied, but do not influence the charge density wave formation on local or global scales. The commensurate charge density wave exhibits long-range order and remains locally intact in the presence of these inhomogeneities.

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B. Campbell, J. V. Riffle, A. de la Torre, Q. Wang, K. W. Plumb, S. M. Hollen. 2023-10-30. Nanoscale electronic inhomogeneities in 1T-TaS$_2$. https://arxiv.org/abs/2310.19751

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