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arXiv · 2605.15566

Charge-dependent scalarization of Einstein- Euler-Heisenberg black holes

Lina Zhang·Yun Soo Myung·De-Cheng Zou·Chao-Ming Zhang·Sheng-Yuan Li
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Abstract

Charge-dependent scalarization of the Einstein-Euler-Heisenberg (EEH) black hole is carried out in the EEH-scalar theory by introducing an exponential scalar coupling with coupling constant $α$ to the Maxwell and nonlinear electrodynamic terms. The bald black hole (EEHBH) is described by mass $M$ and arbitrary magnetic charge $q$ and has a single horizon when choosing the action parameter $μ=0.3$. Here, we find the critical onset charge $q_c=r_+^2/\sqrt{2μ}$ with $r_+(M,q_c)$ the outer horizon radius from the resonance condition. The spontaneous scalarization ($α^+$) of this black hole is available for charge $0 q_c$ and negative $α$. The former case of $q=0.5$ implies infinite branches of scalarized EEHBHs but its fundamental branch ($n=0$) is stable against the $l=0$ modes considered here, while for $q=2$ and $q=20$, one stable scalarized branch is found for each charge within the explored parameter ranges.

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Lina Zhang, Yun Soo Myung, De-Cheng Zou, Chao-Ming Zhang, Sheng-Yuan Li. 2026-09-20. Charge-dependent scalarization of Einstein- Euler-Heisenberg black holes. https://arxiv.org/abs/2605.15566

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