Magnetic Moment Oscillations in a Quantum Hall Ring

Abstract

We predict non-mesoscopic oscillations in the orbital magnetic moment of a thin semiconductor ring in the quantum Hall effect regime. These oscillations, which occur as a function of magnetic field because of a competition between paramagnetic and diamagnetic currents in the ring, are a direct probe of the equilibrium current distribution in the nonuniform quantum Hall fluid. The amplitude of the oscillating moment in a thin ring with major radius $R$ and minor radius (half width) $a$ is approximately $aRe{\omega }_{\mathrm{c}}/c$, where ${\omega }_{\mathrm{c}}$ is the cyclotron frequency.

6 pages, 6 figures, RevTex, 4 GIF animations of the charge and current densities added at http://theo.inrne.bas.bg/~lgeorg/animated-text.html