Combined influence of conical disclination and Rashba spin–orbit coupling on the thermo-magnetic properties of a polar quantum disc

This work presents a theoretical study of the thermodynamic and magnetic response of a geometrically deformed polar quantum disc with conical disclination. The model is based on single-particle motion in a parabolic hard-wall confinement within the effective mass approximation, including Rashba spin–orbit coupling (RSOC) and a magnetic field normal to the disc plane. The exact energy spectrum is derived and employed to calculate the canonical partition function Z, which is then used to determine the internal energy (U), heat capacity (C v ), entropy (S), magnetization (M), magnetic susceptibility ( χ m ), and the magnetocaloric potential ( Δ S). The results show that geometric deformation significantly affects states with finite angular momentum, while the zero-angular-momentum state remains nearly unchanged. The inclusion of RSOC lifts spin degeneracy and induces spin splitting, leading to systematic modifications in the thermo-magnetic behavior. A particularly notable feature is the magnetic field-induced crossover in the χ m from paramagnetic to diamagnetic behavior.