Abstract:
In this thesis, we investigate the thermal stability and thermodynamic
geometries of non-rotating/rotating charged black holes. For these black
holes, we apply Barrow and power-law entropy to determine the physical
quantities such as mass and temperature of the system and find their sta-
bility through first and second phase transitions of the heat capacity. We
analyze the effects of scalar charge Q and hair parameter λ on black holes
properties by taking both positive and negative values of these parame-
ters. It is noted that heat capacity provide the stable, unstable regions and
phase transition points for both black holes. To investigate the thermody-
namic geometry of these black holes, various techniques such as Ruppeiner,
Weinhold, Quevedo and HPEM metrics are considered. It is observed that
Weinhold, Quevedo and HPEM give attrative/repulsive behavior of parti-
cles in stable/unstable regions of black holes.