Analytic phase structures and thermodynamic curvature for the charged AdS black hole in alternative

• 作 者: Zhen-Ming Xu
• 机 构: Institute of Modern Physics,Northwest University,Xi’an 710127,China;School of Physics,Northwest Univ
• 出 处: 物理学前沿
• 发表日期: 2021年2期
• 关键词: thermodynamics of black hole phase transition the Maxwell construction the Ruppe

In this paper,we visit the thermodynamic criticality and thermodynamic curvature of the charged AdS black hole in a new phase space.It is shown that when the square of the total charge of the charged black hole is considered as a thermodynamic quantity,the charged AdS black hole also admits a van der Waals-type critical behavior without the help of thermodynamic pressure and thermody-namic volume.Based on this,we study the fine phase structures of the charged AdS black hole with fixed AdS background in the new framework.On the one hand,we give the phase diagram structures of the charged AdS black hole accurately and analytically,which fills up the gap in dealing with the phase transition of the charged AdS black holes by taking the square of the charge as a thermody-namic quantity.On the other hand,we analyse the thermodynamic curvature of the black hole in two coordinate spaces.The thermodynamic curvatures obtained in two different coordinate spaces are equivalent to each other and are also positive.Based on an empirical conclusion under the framework of thermodynamic geometry,we speculate that when the square of charge is treated as an indepen-dent thermodynamic quantity,the charged AdS black hole is likely to present a repulsive between its molecules.More importantly,based on the thermodynamic curvature,we obtain a universal exponent at the critical point of phase transition.