Vortex Ring and Helical Current Formation in Superconductors Driven by a THz‐Field‐Induced Toroidal Vector Potential

Abstract

Herein, the vortex dynamics in a type II superconducting torus driven by a curl‐free vector potential corresponding to a toroidal moment is studied, which is triggered within picoseconds in an enclosed semiconductor by polarization‐structured THz vector field pulses. Numerical simulations of the time‐dependent Ginzburg–Landau equation in the presence of the toroidal vector potential evidence the formation of vortex ring structures that depend on the toroidal moment strength with a behavior resembling the Little–Parks effect. Applying in addition a static external magnetic flux density, the induced textures in the superconducting phase can be stabilized and steered to form stripe domains with corresponding helical supercurrent density.