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 p_c (1.4 GPa<p_c<1.6 GPa), while the superconducting transition temperature T_c is maximized. T_c 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.