Electrically charged stringy black hole versus magnetically charged stringy black hole in terms of optical properties

This research explores electrically and magnetically charged stringy black holes, calculating their entropy and temperature. It is observed that magnetically charged black holes exhibit a consistent Hawking temperature, unlike electrically charged ones. The study delves into the thermodynamics of black holes, revealing a decrease in Gibbs free energy with increasing charge for electrically charged black holes. Photon motion analysis performed identifies the radial dependence of effective potentials and determines the photon sphere radius which strongly depends on black hole charge. Examining gravitational redshift we have studied frequency shifts and have shown that electric and magnetic charges collectively reduce the redshift of emitted light. The investigation of black hole shadows unveils consistent results for both charge types, with the shadow radius decreasing as the black hole charge increases.