Oscillations of Longitudinal Magnetoresistance in Thin Semiconductor Films With a Parabolic Potential Profile

This paper presents a theoretical study of the longitudinal magnetoresistance in thin semiconductor films with a parabolic potential profile under the influence of a strong quantizing magnetic field. The case of a degenerate electron gas and weak conduction band filling is considered. Based on the kinetic equation, an expression for the longitudinal conductivity is derived, taking into account the spin splitting of Landau levels. A numerical analysis of the resistance behavior for GaAs- and InSb-based structures at a temperature of 4.2 K is performed. It is established that quantum oscillations of magnetoresistance are observed in such nanostructures, and negative longitudinal magnetoresistance occurs even under strong degeneracy conditions. This behavior is caused by quantization of motion in the transverse direction and spin splitting, which makes the system promising for research in the fields of spintronics and magnetoelectronics.