Phys.Rev.D, 105, 104049 (2022)
Echoes from classical black holes
Hyat Huang1, Min-Yan Ou1, Meng-Yun Lai1 and Hong Lü2
1 College of Physics and Communication Electronics, Jiangxi Normal University, Nanchang 330022, China.
2 Center for Joint Quantum Studies, Department of Physics, School of Science, Tianjin University, Tianjin 300350, China.
* mengyunlai@jxnu.edu.cn
Abstract
We study echoes of free massless scalar from dyonic black holes in Einstein-Maxwell gravity extended with the quasi-topological electromagnetic term. These asymptotically- at black holes all satisfy the dominant energy condition. We find that for suitable parameters, the effective potential can have double peaks and consequently echoes of quasinormal modes arise. In general the echo frequency associated with the initial wave packet released inside the two peaks is about twice the frequency of the one released outside.
