Half-quantum flux in spin-triplet superconducting rings with bias current

TL;DR

This paper theoretically demonstrates that a bias current can stabilize a half-quantum-flux state in spin-triplet superconducting rings, revealing a field-induced shift in Little-Parks oscillations with potential experimental relevance.

Contribution

It introduces a theoretical model showing how bias current stabilizes half-quantum-flux states via Zeeman and spin-orbit couplings in superconducting rings.

Findings

Bias current stabilizes half-quantum-flux states.

Half-quantum-shift observed in Little-Parks oscillations.

Relevance to recent experimental observations.

Abstract

Effects of a bias electric current have been theoretically investigated in a spin-triplet superconducting ring in a magnetic field. Based on the Ginzburg-Landau theory, we show that the bias current can stabilize a half-quantum-flux (HQF) state via couplings to the Zeeman field and the dipole-type spin-orbit interaction, the latter becoming active when the field is tilted from the ring axis. The emergence of the HQF state is reflected as a field-induced half-quantum-shift in the Little-Parks (LP) oscillation in the critical current. Possible relevance to recent LP experiments is also discussed.