Effect of chromium doping on superconductivity and charge density wave order in the kagome metal Cs(V1-xCrx)3Sb5

The recently discovered kagome metal AV3Sb5 (A = K, Rb, Cs) with intertwined superconductivity and charge density wave (CDW) order has attracted considerable interest. Here we investigate the evolution of CDW and superconductivity in Cs(V1-xCrx)3Sb5, where chromium substitution for vanadium introduces extra electron carriers. Our experiments reveal that the CDW order is gradually suppressed under chromium doping, which can be understood from the band structure modifications induced by electron doping. This highlights the importance of the van Hove singularities near the M and L points for CDW instability. The anomalous Hall effect that is coupled with CDW in CsV3Sb5 only appears in lightly doped Cs(V1-xCrx)3Sb5 and vanishes at x 0.06 when the CDW order remains relatively strong. Unlike hole- and isovalent-doped AV3Sb5, where superconductivity is enhanced upon suppression of CDW, superconductivity is rapidly suppressed under chromium doping, pointing to a conventional s-wave pairing.