Charge Density Wave Order and Fluctuations above T_CDW and below Superconducting T_c in the Kagome Metal CsV₃Sb_5-xSn_x

The newly discovered kagome metal system AV₃Sb₅ (A = K, Rb, Cs) features both superconducting and charge density wave (CDW) instabilities, and provides a platform for a variety of exotic quantum phenomena that motivate their great current interest. We present a comprehensive set of measurements, including x-ray, bulk magnetization and specific heat measurements, over a broad range of temperatures from 300 K to 2 K on the kagome metal CsV₃Sb₅ and its hole-doped variation CsV₃Sb_5-xSn_x in single crystal form, allowing us to reveal the temperature evolution of the CDW state and the co-existence of the CDW with superconductivity at low temperatures.