Lorentz violation serves as a significant feature in many modified theories of gravity. In particular, spontaneous Lorentz violation induced by the Kalb-Ramond field has attracted considerable attention. Recently, an electrically charged black hole solution within the Kalb-Ramond framework was proposed. In this study, we investigate the quasinormal modes of the resulting ``undecouplable'' system using both the matrix-valued continued fraction method and the matrix-valued direct integration method. Additionally, we develop a new approach to distinguish between different modes in such ``undecouplable'' systems. An error analysis is performed, and the influence of Lorentz violation on the fundamental quasinormal modes is systematically analyzed within a suitable parameter range.
@article{arxiv.2509.23732,
title = {Quasinormal modes of an electrically charged Kalb-Ramond black hole},
author = {Yun-Tao Gu and Wen-Di Guo and Yu-Xiao Liu},
journal= {arXiv preprint arXiv:2509.23732},
year = {2025}
}