NED-AdS black holes, extended phase space thermodynamics and Joule--Thomson expansion

We study and discuss the critical behavior of charged by nonlinear electrodynamics (NED) AdS black holes in an extended phase space. The negative cosmological constant is treated as a thermodynamic pressure and the black hole mass is considered as the chemical enthalpy. We show the analogy of thermodynamics and phase transitions studied with the Van der Waals liquid-gas system. We introduce new thermodynamic quantities conjugated to the NED coupling and a magnetic charge. It was demonstrated that the first low of black hole thermodynamics and the Smarr relation hold. We have calculated the Joule--Thomson thermodynamic coefficient and inversion temperature and the Joule--Thomson adiabatic expansion is investigated.