Superradiant instability of dyonic Reissner-Nordstrom black holes

Abstract: We investigate the superradiant instability of dyonic Reissner-Nordstr\"{o}m (dRN) black holes with two charges under a charged massive scalar perturbation. Two conditions for possessing a trapping well are obtained from analyzing asymptotic scalar potential and far-region wave functions. It is clear that the superradiant instability is not allowed in the dRN black holes because the conditions for a trapping well are not compatible with the superradiance condition.