Study of Thermomagnetic Properties for Non-Relativistic Particle with Position Dependent Mass in the Presence of Topological Defect and External Magnetic Field: Theory and Simulation

The thermodynamic and magnetic properties of a particle confined by an exponential potential were studied in the non-relativistic quantum mechanics framework with topological defect. The perturbation effect of an external magnetic field to the system which formulated with the Schrodinger equation is also investigated. It’s shown by using the suitable Greene–Aldrich approximation and asymptotic iteration method, the analytical approximate energy eigenvalue of the radial part is obtained theoretically. The energy spectra were calculated and simulated with the variation of quantum number, topological defect parameter, potential parameter, and external magnetic field. The appearance of topological defect caused the particle becomes more bound since it decreased the energy level. Subsequently, the energy eigenvalue equation was applied to obtain the partition function of the system with the purpose to evaluate and to calculate the thermomagnetic properties of H₂, LiH, and RbH diatomic molecules. The vibrational mean energy and entropy grow exponentially by the influence of the external magnetic field so that the molecule becomes unstable. The perturbation of the external magnetic field causes the value of the free energy increases and the stability of the system is getting worse, especially in areas with a large magnetic field influence. The magnetic susceptibility of the system always has a positive value and indicating ferromagnetic characteristics of the molecules in this system.