Triple points and novel phase transitions of dyonic AdS black holes with quasitopological electromagnetism

Abstract

The quasi-topological electromagnetism has an important influence on the strong gravity of the dyonic black hole. For example three photon spheres with one being stable are found and which is wished to be tested with the observation of EHT. In this paper, we mainly concern the thermodynamics and phase transition for the dyonic AdS black hole when the quasi-topological electromagnetism is included. Quite different from the black hole solution without the quasi-topological electromagnetism, we observe a triple point phase structure by varying the coupling parameters. Of particular interest, in some certain parameter values, two separated coexistence curves are present, which is also an additional novel phase structure that absents in the black hole solution without the quasi-topological electromagnetism. While the critical exponents share the same values with the mean field theory. These results uncover the intriguing properties of the dyonic AdS black holes with quasi-topological electromagnetism from a thermodynamic point of view.

$${\textbf{D}}$$-dimensional dyonic AdS black holes with quasi-topological electromagnetism in Einstein Gauss–Bonnet gravity

“…An overview of dyonic fields is dedicated to experiencing the situation of a purely electric source [1] with a part of the magnetic field together in a quasi-topological electromagnetism [51,52]. However, a convenient choice for the gauges fields should be in the following form…”

Joule-Thomson expansion of AdS black holes in quasi-topological electromagnetism

“…It is now possible to write the thermodynamical quantities related to the black hole [49]. Considering r + as the largest root of f (r + ) = 0 and the negative cosmological constant as positive pressure P = − Λ 8π then the temperature and the entropy are…”

“…The aim of this paper is to present the study of the Joule-Thomson in quasi-topological electromagnetism [48], a theory that corresponds to a higher-order extension of Maxwell electromagnetism constructed with the bilinear invariant F 2 = F µν F µν . In [48] the authors also found the corresponding charged AdS black hole and their thermodynamics phase transitions were presented in [49].…”

Dyonic Ads Black Holes with Quasi-Topological Electromagnetism in $4\-D$ Einstein Gauss-Bonnet Gravity

“…An overview of dyonic fields is dedicated to experiencing the situation of a purely electric source [28] with a part of the magnetic field together in a quasi-topological electromagnetism [29,30]. Indeed, We think about the following constraints:…”