A ferroelectric‐superconducting photodetector

A ferroelectric‐superconducting photodetector has been developed and characterized. An atomically ordered PbZrTiO3 (PZT) ferroelectric gate was grown over a c‐oriented YBa2Cu3O7−x (YBCO) high Tc superconductor substrate by excimer laser deposition. Irradiation of the PZT gate with photons near the ferroelectric gap energy resulted in a measurable change of the drain‐source photocurrent with the device at a temperature near Tc of the YBCO. The critical temperature of the YBCO base was shifted up to 4 K when the PZT gate was irradiated with photon flux of wavelength from 300 to 500 nm. A responsivity of 360 A/W was measured and an upper bound on response time to optical irradiation of 100 ns was determined.