Light-triggered pulsed electricity generation using interfacial polarization in heterostructures

Polarization within materials and interfaces is subject to modulation by external stimulation, thereby leading to distinctive phenomena, including both the pyroelectric effect and piezoelectric effect. However, light-induced variations in polarization and the resultant effects and associated electric outputs have been largely overlooked, in particular at interfaces. We report that a light-induced variation of the interfacial polarization can produce a pronounced pulsed current, with a high current density of 263.5 μA cm –2 and an ultrafast response time of 32 μs, resulting in significant enhancements in both current density and response time compared to the interfacial pyroelectric effect. In particular, this phenomenon can be observed at interfaces between various ferroelectric materials and Sb 2 Se 3 films, where a PZT/Sb 2 Se 3 interface exhibits the highest light-induced charge variation coefficient of 38.2 mC m –2 W –1 . Our study establishes a new paradigm for understanding the influence of light on interfacial polarization, thereby significantly enhancing fundamental research on polarity changes in heterostructures for ultrasensitive light detection.