Revealing the competition between charge density wave and superconductivity in CsV3Sb5 through uniaxial strain

The authors apply uniaxial strain on the layered kagome superconductor CsV${}_{3}$Sb${}_{5}$. They show that its charge density wave (CDW) and superconductivity (SC) transitions are dominated by the change in the $c$ axis, and the effect of the explicit rotational symmetry breaking by strain is negligible on the competition between CDW and SC. Together with theoretical studies, they propose that the trilinear coupling between the ${M}_{1}^{+}$ and ${L}_{2}^{\ensuremath{-}}$ phonon modes plays an important role in the CDW.