Tunable anisotropic nonlinearity in superconductors with asymmetric antidot array

The influence of the spatial asymmetry of the pinning potential on the spectral composition of the voltage, induced in perforated superconducting Al bridges by the injection of a sinusoidal bias current, was investigated. The loss of the mirror symmetry of the pinning potential leads to the appearance of even Fourier components in the induced voltage in the vicinity of the superconducting phase transition line on the H-T diagram (H is the external magnetic field, and T is the temperature). Artificially-introduced asymmetry for vortex motion makes it possible to create low-resistive materials, in which nonlinearity depends on the direction of injected electrical currents.