Philosophical magazine b-physics of condensed matter statistical mechanics electronic optical and magnetic properties vol:80 issue:5 pages:847-856
Shapiro voltage steps at voltages V-n=nV(o) occur in the voltage-current characteristics of a superconducting film with a periodic pinning potential in the presence of rf radiation. We report on their experimental observation in a superconducting film with a square lattice of perforated microholes (antidots) and on numerical simulations showing the Shapiro steps in the voltage-current characteristics of the de flux transformer. For the square antidot lattice, the ratio V-o/v of the step height to the applied rf frequency depends on the antidot lattice period d, while in the flux transformer geometry this ratio can be tuned by the magnetic field. This tuneability of the resolution makes the flux transformer a good candidate for applications (e.g. broad-band radiation detection).