Highly sensitive and wideband optical detection in patterned YBa2Cu3O7−δ thin films

Abstract

We have measured the optical responses up to 18 GHz in patterned YBa2Cu3O7−δ thin films at various wavelengths by optical heterodyne mixing. The responsivity of the detectors is higher than 50 V/W below 1 Hz at various wavelengths and the responsivity is 20 mV/W at 780 nm and 150 mV/W at 1.55 μm wavelengths in the regime of the modulation frequency from 3 GHz to 18 GHz.