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arXiv · 1812.01368

Incommensurate Chiral CDW in $1T$-VSe$_2$

Y. Sugawara·A. Nomura·Y. Toda·T. Kurosawa·M. Oda·T. Matsuura·K. Ichimura·S. Tanda
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Abstract

We have investigated the chiral charge-density wave (CDW) in $1T$-VSe$_2$ using scanning tunneling microscopy (STM) measurements and optical polarimetry measurements. With the STM mesurements, we revealed that the CDW intensities along each triple-$q$ directions are different. Thus the rotational symmetry of $1T$-VSe$_2$ is lower than that in typical two-dimentional triple-$q$ CDWs. We found that the CDW peaks form a kagome lattice rather than a triangular lattice. The Friedel oscillations have the chirality and the periodicity reflected properties of the background CDW. With the optical measurements in $1T$-VSe$_2$, we also observed a lower rotational symmetry with the polarization dependence of the transient reflectivity variation, which is consistent with the STM result on a microscopic scale. Both $1T$-TiSe$_2$ and $1T$-VSe$_2$ show chiral CDWs, which implies that such waves are usual for CDWs with the condition $H_\mathrm{CDW} \equiv q_{1}\cdot(q_{2} \times q_{3}) \neq0$.

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Y. Sugawara, A. Nomura, Y. Toda, T. Kurosawa, M. Oda, T. Matsuura, K. Ichimura, S. Tanda. 2018-12-04. Incommensurate Chiral CDW in $1T$-VSe$_2$. https://arxiv.org/abs/1812.01368

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