Abstract

Abstract Recently, the coexistence and competition of superconductivity (SC) and charge density wave (CDW) have emerged in Kagome superconductor AV3Sb5 (A=K, Rb, Cs) under pressure, which has aroused widespread interest. Here, chemical substitution is used to introduce chemical pressure to further investigate the coexistence and competition between CDW and SC states. By preparing CsV3(Sb1-xSx)5series single crystals and studying their crystal structure, chemical valence states, superconductivity, and electronic transport behavior, it is found that S doping causes significant chemical pressure that is similar to axial mechanical pressure, resulting in suppression on the CDW and enhancement on SC. The Tc-x relationship exhibits a double dome superconductivity, similar to the behavior observed in the CsV3Sb5 under mechanical pressure. In addition, a negative correlation between TCDWand the disorder degree (measured by residual resistivity) is observed. This correlation is consistent with the observed translational jump in the ρ(T) curve before and after the CDW transition, that is, the temperature coefficient of resistivity does not change before and after the CDW phase transition, but only the resistivity curve shifts to a certain value. This phenomenon reveals that disorder is an important factor affecting the CDW transition of the system. Further, S doping also induces hole band filling effect that results in a decrease in the DOS at EFand consequently counterbalances the Tc enhancement effect from chemical pressure to a certain extent. The electronic phase diagram of the CsV3(Sb1-xSx)5system is accordingly established, which demonstrates the correlation between the SC, CDW, disorder degree, and other electronic nature of the system.