Carrier Injection and Manipulation of Charge-Density Wave in Kagome Superconductor CsV3Sb5

Kagome metals AV(3)Sb(5) (A = K, Rb, and Cs) exhibit a unique superconducting ground state coexisting with charge-density wave (CDW), whereas how these characteristics are affected by carrier doping remains unexplored because of the lack of an efficient carrier-doping method. Here we report successful electron doping to CsV3Sb5 by Cs dosing, as visualized by angle-resolved photoemission spectroscopy. We found that the electron doping with Cs dosing proceeds in an orbital-selective way, as characterized by a marked increase in electron filling of the Sb 5p(z) and V 3d(xz/yz) bands as opposed to the relatively insensitive nature of the V 3d(xy)/x(2)-y(2) bands. By monitoring the temperature evolution of the CDW gap around the (M) over bar point, we found that the CDW can be completely killed by Cs dosing while keeping the saddle point with the V 3d(xy)/x(2)-y(2) character almost pinned at the Fermi level. The present result suggests a crucial role of multiorbital effect to the occurrence of CDW and provides an important step toward manipulating the CDW and superconductivity in AV(3)Sb(5).

Automated summary

Successful electron doping to CsV3Sb5 by Cs dosing has been achieved, and the electron filling of the Sb 5p(z) and V 3d(xz/yz) bands can be selectively increased while suppressing the CDW. This result reveals the crucial role of multiorbital effect in CDW and superconductivity.