Dibakar Roychowdhury

Analytic study of properties of holographic superconductors in Born-Infeld electrodynamics

A bstractIn this paper, based on the Sturm-Liouville eigenvalue problem, we analytically investigate several properties of holographic s-wave superconductors in the background of a Schwarzschild-AdS spacetime in the framework of Born-Infeld electrodynamics. Based on a perturbative approach, we explicitly find the relation between the critical temperature and the charge density and also the fact that the Born-Infeld coupling parameter indeed affects the formation of scalar hair at low temperatures. Higher value of the Born-Infeld parameter results in a harder condensation to form. We further compute the critical exponent associated with the condensation near the critical temperature. The analytical results obtained are found to be in good agreement with the existing numerical results.

New type of phase transition in Reissner Nordström–AdS black hole and its thermodynamic geometry

Abstract The phase transition of a RN–AdS black hole is studied in details using Ehrenfests equations. There is no discontinuity in entropy which signals a lack of any first order phase transition. We then show that although Ehrenfests first equation is satisfied, the second is not, so that a true second order phase transition is also ruled out. However this deviation from the second Ehrenfests equation, for a certain range of the black hole charge, indicates the existence of a new glassy type transition. We finally study the thermodynamic behaviour using state space geometry and find that the scalar curvature diverges exactly at those points where the heat capacity diverges.

Critical phenomena in Born-Infeld AdS black holes

We investigate the thermodynamics of critical phenomena in Born-Infeld AdS black holes using a canonical ensemble. The critical behavior has been studied near the critical point which is characterized by a discontinuity in the heat capacity at constant charge. We explicitly calculate the critical exponents of the relevant thermodynamic quantities. These exponents satisfy all the thermodynamic scaling laws. We also check the Generalized Homogeneous Function (GHF) hypothesis (or the scaling hypothesis) which is shown to be compatible with the thermodynamic scaling laws. Finally we check the validity of the scaling laws of second kind which include the critical exponents associated with the spatial correlation. In the appropriate limit our results also provide the corresponding expressions for the Reissner Nordstrom AdS case.

A unified picture of phase transition: from liquid-vapour systems to AdS black holes

A bstractBased on fundamental concepts of thermodynamics we examine phase transitions in black holes defined in Anti-de Sitter (AdS) spaces. The method is in line with that used a long ago to understand the liquid-vapour phase transition where the first order derivatives of Gibbs potential are discontinuous and Clausius-Clapeyron equation is satisfied. The idea here is to consider the AdS black holes as grand-canonical ensembles and study phase transition defined by the discontinuity of second order derivatives of Gibbs potential. We analytically check that this phase transition between the ‘smaller’ and ‘larger’ mass black holes obey Ehrenfest relations defined at the critical point and hence confirm a second order phase transition. This include both the rotating and charged black holes in Einstein gravity.

Effect of external magnetic field on holographic superconductors in presence of nonlinear corrections

In this paper, based on analytic technique, several properties of holographic

Thermodynamics of phase transition in higher dimensional AdS black holes

s

Analytic study of Gauss-Bonnet holographic superconductors in Born-Infeld electrodynamics

-wave superconductors have been investigated in the presence of various higher derivative (\textit{non linear}) corrections to the usual Maxwell action. Explicit expressions for the critical temperature and the condensation values have been obtained in the probe limit. Finally, the nature of condensate solutions have been investigated by immersing the superconductor in an external magnetic field. It is found that below certain critical magnetic field strength (

Critical behavior of Born-Infeld AdS black holes in higher dimensions

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Ehrenfest’s scheme and thermodynamic geometry in Born-Infeld AdS black holes

) there exists a superconducting phase. Most importantly it has been observed that the value of this critical field strength (

AdS/CFT superconductors with Power Maxwell electrodynamics: Reminiscent of the Meissner effect

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