Damping of dHvA oscillations and vortex-lattice disorder in the peak-effect region of strong type-II superconductors

TL;DR

This paper investigates how vortex lattice disorder in strong type-II superconductors near the peak-effect region causes additional damping of de Haas-van Alphen oscillations, revealing a link between vortex disorder and quasiparticle scattering.

Contribution

It provides experimental evidence connecting vortex lattice disorder with increased damping of quantum oscillations in the superconducting state, clarifying a controversial aspect.

Findings

Sharp drop in dHvA amplitude below Hc2 correlates with vortex lattice disorder.

Enhanced vortex disorder increases quasiparticle scattering.

Vortex lattice disorder significantly affects quantum oscillation damping.

Abstract

The phenomenon of magnetic quantum oscillations in the superconducting state poses several questions that still defy satisfactory answers. A key controversial issue concerns the additional damping observed in the vortex state. Here, we show results of \mu SR, dHvA, and SQUID magnetization measurements on borocarbide superconductors, indicating that a sharp drop observed in the dHvA amplitude just below H_{c2} is correlated with enhanced disorder of the vortex lattice in the peak-effect region, which significantly enhances quasiparticle scattering by the pair potential.