Thermodynamics and the Joule-Thomson expansion of dilaton black holes in 2+1 dimensions

Abstract

In this paper, we study thermodynamics and its applications to the static charged dilaton black hole in 2+1 dimensions. We compute the first law and the Smarr relations for the black hole and introduce a new thermodynamical parameter in order to satisfy the first law. We compute specific heat capacities, internal energy and free energy for the black hole and study local and global stability of the black hole. For N = 1, the black hole is locally stable for all values of the horizon radius and does not go through phase transitions. Maxwell`s relations are presented for this case. For N = 6/7, small black holes are locally stable and large black holes are not. There is a first order phase transition between small black holes and the thermal AdS space. We have also studied the Joule-Thomson expansion for black holes with N = 1. It is also noted that unlike the charged BTZ black hole, the charged dilaton black hole does not violate the Reverse Isoperimetric Inequality for certain values of parameters of the theory.Comment: 26 pages, 12 figure