Field dependence of the vortex-core size in dirty two-band superconductors

Abstract

We study the structure of Abrikosov vortices in two-band superconductors for different external magnetic fields and different parameters of the bands. The vortex core size determined by the coherence lengths are found to have qualitatively different behaviour from that determined by the quasiparticle density of states spatial variation. These different vortex core length scales coincide near the upper critical field, while the discrepancy between them becomes quite significant at lower fields. Within the diffusive approximation we demonstrate several generic regimes in the field dependence of the vortex core sizes determined by the disparity of diffusion constants in the two bands.

Multiband Superconductors: Two Characteristic Lengths for Each Contributing Condensate

“…The local relation between the zero-energy local DOS and the gap function is well-known only for the diffusive regime near the upper critical magnetic field 25 . At lower fields the situation is significantly more complicated, especially in multiband superconducting materials [26][27][28] .…”

Multiband Superconductors: Two Characteristic Lengths for Each Contributing Condensate

“…The local relation between the zero-energy local DOS and the gap function is well-known only for the diffusive regime near the upper critical magnetic field . At lower fields, the situation is significantly more complicated, especially in multiband superconducting materials. − …”