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

Kagome metals AV3Sb5 (A = K, Rb, and Cs) exhibit a unique superconducting\nground state coexisting with charge-density wave (CDW), whereas how these\ncharacteristics are affected by carrier doping remains unexplored because of\nthe lack of an efficient carrier-doping method. Here we report successful\nelectron doping to CsV3Sb5 by Cs dosing, as visualized by angle-resolved\nphotoemission spectroscopy. We found that the electron doping with Cs dosing\nproceeds in an orbital-selective way, as characterized by a marked increase in\nelectron filling of the Sb 5pz and V 3dxz/yz bands as opposed to relatively\ninsensitive nature of the V 3dxy/x2-y2 bands. By monitoring the temperature\nevolution of the CDW gap around the M point, we found that the CDW can be\ncompletely killed by Cs dosing while keeping the saddle point with the V\n3dxy/x2-y2 character almost pinned at the Fermi level. The present result\nsuggests a crucial role of multi-orbital effect to the occurrence of CDW, and\nprovides an important step toward manipulating the CDW and superconductivity in\nAV3Sb5.\n