Evolution of superconductivity and charge order in pressurized RbV3Sb5

The kagome metals AV3Sb5 (A =K,Rb,Cs) under ambient pressure exhibit an unusual charge order,from which superconductivity emerges.In this work,by applying hydrostatic pressure using a liquid pressure medium and carrying out electrical resistance measurements for RbV3Sb5,we find that the charge order becomes suppressed under a modest pressure Pc (1.4 GPa＜ Pc ＜ 1.6 GPa),while the superconducting transition temperature Tc is maximized.Tc is then gradually weakened with further increase of pressure and reaches a minimum around 14.3 GPa,before exhibiting another maximum around 22.8 GPa,signifying the presence of a second superconducting dome.Distinct normal state resistance anomalies are found to be associated with the second superconducting dome,similar to KV3Sb5.Our findings point to qualitatively similar temperature-pressure phase diagrams in KV3Sb5 and RbV3Sb5,and suggest a close link between the second superconducting dome and the high-pressure resistance anomalies.