New Mechanism of Quantum Oscillations in the Suprcpnducing Mixed State (Hc1<<B<<Hc2)

TL;DR

This paper proposes a novel mechanism for quantum oscillations in the mixed state of superconductors, explaining enhanced de Haas-van Alphen oscillations at fields much lower than Hc2 due to inhomogeneity-induced energy sorting.

Contribution

It introduces a new mechanism based on inhomogeneity and energy sorting in vortex lattices that explains quantum oscillation behavior in superconductors.

Findings

Enhanced quantum oscillations at B<<Hc2 explained by the mechanism.

Inhomogeneity causes energy-based localization and motion of excitations.

Mechanism potentially explains slow decay of oscillations below Hc2.

Abstract

We argue that inhomogeneity inherent to the presence of periodic supercurrents in the vortex lattice sorts excitations by energies into the ones that are spatially localized and those that perform motion along large Larmour orbits. This energy threshold results in a new mechanism for the de Haas-van Alphen oscillations which enhances oscillations at B<<Hc2, even for an isotropic superconductor with a constant gap. We suggest that the mechanism is of a general character and can cause the slow decay of the de Haas-van Alphen effect when the field, B, decreases below Hc2.