Structure of the kagome superconductor <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>CsV</mml:mi><mml:mn>3</mml:mn></mml:msub><mml:msub><mml:mi>Sb</mml:mi><mml:mn>5</mml:mn></mml:msub></mml:mrow></mml:math> in the charge density wave state
Yuxin Wang, Tao Wu, Zheng Li, Kun Jiang, Jiangping Hu
Abstract
The structure of charge density wave states in ${A\mathrm{V}}_{3}{\mathrm{Sb}}_{5}$ ($A$ = K, Rb, Cs) kagome superconductors remains elusive, with three possible $2a\ifmmode\times\else\texttimes\fi{}2a\ifmmode\times\else\texttimes\fi{}2c$ candidates: trihexagonal, star-of-David, and their mixture. In this study, we conducted a systematic first-principles investigation of the nuclear quadrupole resonance (NQR) and nuclear magnetic resonance (NMR) spectra for the $2a\ifmmode\times\else\texttimes\fi{}2a\ifmmode\times\else\texttimes\fi{}2c\phantom{\rule{4pt}{0ex}}{\mathrm{CsV}}_{3}{\mathrm{Sb}}_{5}$ structures. By comparing our simulations with experimental data, we have concluded that the NQR spectrum indicates the trihexagonal structure as the proper structure for ${\mathrm{CsV}}_{3}{\mathrm{Sb}}_{5}$ after its charge density wave phase transition. The NMR calculation results obtained from the trihexagonal structure are also consistent with the experimental data.