Magnetoresistance and electric current oscillations induced by geometry in a two-dimensional quantum ring

In this work, we investigate the effects of a controlled conical geometry on the electric charge transport through a two-dimensional quantum ring weakly coupled to both the emitter and the collector. These mesoscopic systems are known for being able to confine highly mobile electrons in a defined region of matter. In particular, we consider a GaAs device having an average radius of 800 nm in different regimes of subband occupation at non-zero temperature and under the influence of a weak and uniform background magnetic field. Using an adapted Landauer formula for resonant tunneling together with the corresponding energy eigenvalues we explore how the modified surface affects the Van-Hove conductance singularities, the magnetoresistance interference patterns resulting from the Aharonov-Bohm oscillations of different frequencies and the charge transport when an electric potential is applied to the terminals of the device. Magnetoresistance and charge current oscillations depending only on the curvature intensity are reported, providing a new feature that represents an alternative way to optimize the transport through the device by tuning its geometry. • Conical curvature reshapes the transport spectrum of a 2D GaAs quantum ring. • Geometry tunes Van Hove conductance peaks and Aharonov–Bohm interference patterns. • Magnetoresistance exhibits curvature-controlled oscillations, including stable node regimes. • A nearly periodic magnetoresistance modulation with curvature is identified at zero field. • The charge current shows geometry-driven oscillations and a sawtooth-like behavior at high bias.