Abstract
In this paper, we study spontaneous scalarization of asymptotically anti-de Sitter charged black holes in an Einstein–Maxwell-scalar model with a non-minimal coupling between the scalar and Maxwell fields. In this model, Reissner–Nordström-AdS (RNAdS) black holes are scalar-free black hole solutions, and may induce scalarized black holes due to the presence of a tachyonic instability of the scalar field near the event horizon. For RNAdS and scalarized black hole solutions, we investigate the domain of existence, perturbative stability against spherical perturbations and phase structure. In a micro-canonical ensemble, scalarized solutions are always thermodynamically preferred over RNAdS black holes. However, the system has much richer phase structure and phase transitions in a canonical ensemble. In particular, we report a RNAdS BH/scalarized BH/RNAdS BH reentrant phase transition, which is composed of a zeroth-order phase transition and a second-order one.
Highlights
We investigated spontaneous scalarization of asymptotically AdS charged black holes in an EMS model, and studied phase structure of scalarized and RNAdS black holes in a canonical ensemble
We focused on a non-minimal coupling function f (φ) = eαφ2, which leads to spontaneous scalarization due to the tachyonic instability of the scalar field near the event horizon
Scalarized black holes can be induced from RNAdS black holes on the bifurcation line, which consists of zero modes of the scalar perturbation in RNAdS black holes
Summary
We derive the equations of motion, asymptotic behavior, the Smarr relation and the Helmholtz free energy for asymptotically AdS scalarized black hole solutions in the EMS model. The action of the EMS model with a negative cosmological constant is. Where we take G = 1 for simplicity throughout this paper. In the action (1) , the scalar field φ is minimally coupled to the metric gμν and non-minimally coupled to the gauge field Aμ, Fμν = ∂μ Aν − ∂ν Aμ is the electromagnetic field strength tensor, = −3/L2 is the cosmological constant with the AdS radius L, and f (φ) is the non-minimal coupling function of the scalar and gauge fields
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
