High-performance solar-blind photodetector based on Sm-doped perovskite rare-earth nickelate heterojunctions

Solar-blind photodetectors based on wide bandgap semiconductors have attracted great interest recently. Perovskite rare-earth nickelates like RNiO₃ are stable p-type semiconductors with adjustable physical properties. This paper reports a high-performance solar-blind photodetector made of Pr_xSm_1−xNiO₃/Nb:SrTiO₃ heterojunctions utilizing a lateral photovoltaic effect. A high position sensitivity of up to 879.4 mV/mm and a fast relaxation time of 0.6 μs were observed with 266 nm laser irradiation under 3 Suns. The transverse diffusion model of photogenerated carriers can explain the lateral photovoltaic effect well. Furthermore, an optical communication system transmission was developed from the junction. The fast relaxation time and high position sensitivity make the rare-earth nickelates a promising candidate for a self-powered high-performance solar-blind detector.