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arXiv · 2112.15288

Tri-Hexagonal charge order in kagome metal CsV$_{3}$Sb$_{5}$ revealed by $^{121}$Sb NQR

Chao Mu·Qiangwei Yin·Zhijun Tu·Chunsheng Gong·Ping Zheng·Hechang Lei·Zheng Li·Jianlin Luo
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Abstract

We report $^{121}$Sb nuclear quadrupole resonance (NQR) measurements on kagome superconductor CsV$_3$Sb$_5$ with $T_{\rm c}=2.5$ K. $^{121}$Sb NQR spectra split after a charge density wave (CDW) transition at $94$ K, which demonstrates a commensurate CDW state. The coexistence of the high temperature phase and the CDW phase between $91$ K and $94$ K manifests that it is a first order phase transition. The CDW order exhibits Tri-Hexagonal deformation with a lateral shift between the adjacent kagome layers, which is consistent with $2 \times 2 \times 2$ superlattice modulation. The superconducting state coexists with CDW order and shows a conventional s-wave behavior in the bulk state.

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Chao Mu, Qiangwei Yin, Zhijun Tu, Chunsheng Gong, Ping Zheng, Hechang Lei, Zheng Li, Jianlin Luo. 2021-12-31. Tri-Hexagonal charge order in kagome metal CsV$_{3}$Sb$_{5}$ revealed by $^{121}$Sb NQR. https://doi.org/10.1088/1674-1056%2Fac422c

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