Work

Chaos bound violation and greybody factors of charged-AdS black holes surrounded by dark matter halos and quintessence

Year: 2026

Type: article

Abstract: In this work, we investigate the properties of a charged anti-de Sitter (AdS) black hole (BH) in the presence of a Dehnen-type dark matter halo and a surrounding quintessence field. Starting from the modified Einstein field equations, we construct the corresponding BH solutions by incorporating the effects of electric charge, negative cosmological constant, dark matter distribution, and quintessence characterized by a variable equation of state. We analyze the resulting spacetime geometry through the behavior of the metric function and horizon structure, demonstrating that the dark matter halo enhances the gravitational attraction while the quintessence field introduces a repulsive contribution that significantly modifies the asymptotic structure. The effective potential is used to analyze the geodesic motion of test particles, revealing that dark matter deepens the potential well and stabilizes bound orbits, whereas quintessence weakens orbital confinement. Furthermore, we compute the greybody factor (GBF) to explore the impact of these fields on Hawking radiation, showing that quintessence and electric charge enhance the transmission probability, while the dark matter halo suppresses it by increasing the effective potential barrier. We study the chaos bound through the Lyapunov exponent and demonstrate that the interplay between charge and quintessence can lead to violations of the bound, whereas the dark matter halo tends to restore stability and preserve the bound. Finally, we investigate the strong-field optical properties of the BH, demonstrating how the electric charge and quintessence parameter influence the critical shadow scale, photon-sphere radius, and innermost stable circular orbit, with potential implications for observational constraints from Sgr A*.

Source: Physics Letters B

DOI: 10.1016/j.physletb.2026.141094

Authors: Muhammad Yasir, Faisal Javed, Chuanzhong Li, M. Zeeshan Gul, Sulaman Shaukat