Scalarized black holes in the Einstein-Maxwell-scalar theory with a quasi-topological term

TL;DR

This paper explores scalarized charged black holes within the Einstein-Maxwell-scalar theory incorporating a quasi-topological term, revealing infinite families of solutions with varying stability properties based on their excitation level.

Contribution

It introduces new classes of scalarized black holes in a modified gravity theory with exponential couplings, classifies them by excitation number, and analyzes their stability.

Findings

Infinite scalarized black hole solutions classified by excitation number.

Fundamental black holes are stable, higher excited states are unstable.

The theory extends understanding of black hole scalarization with a quasi-topological term.

Abstract

We investigate the Einstein-Maxwell-scalar theory with a quasi-topological term. Considering exponential couplings to Maxwell term, quasi-topological term, and both terms, we obtain three sets of infinite scalarized charged black holes by taking into account tachyonic instability of dyonic Reissner-Nordstr\"{o}m black hole. Each set of infinite scalarized charged black holes is classified by the number of $n=0,1,2,\cdots$, where $n=0$ is called the fundamental black hole and $n=1,2,\cdots$ denote the $n$-excited black holes. All $n=0$ black holes are stable against the radial perturbation, while all $n=1,2$ black holes are unstable.