Spatio-temporal superconducting dynamics driven by THz fields from topological spintronic terahertz emitters

Sci Rep. 2022 Sep 16;12(1):15610. doi: 10.1038/s41598-022-16377-y.

Abstract

Metastructures of spintronic THz emitters can be engineered to have a well-defined topology characterized by a topological charge. The emitted THz radiation possesses a phase-locked transversal and longitudinal components with the ratio of which being tunable by the topological charge of the underlying metastructure. The THz fields so produced are employed to drive and spatio-temporally modulate the superconducting order parameter in a type II superconductor. Using a time-dependent Landau-Ginzburg approach, it is demonstrated how the topology of the THz fields is reflected in a texturing of the superconducting phase and density. Full numerical simulations illustrate the emergence and the nanoscale steering of Abrikosov vortices as well as the local modification of the superconducting density and transport properties of nanoscale samples with different geometries. The study highlights the potential of metamaterials based on spintronic THz emitters as a coherent source for spatially and vectorially modulated THz radiation.