Solar blind photoconductivity in three-terminal devices of LaAlO3/SrTiO3 heterostructures.

We report observations of photoconductivity in ultrathin films of LaAlO(3) grown on (001) SrTiO(3) at several deposition temperatures. The films show pronounced metallic behavior in the dark. The conductance of this metallic state can be enhanced by ultraviolet light (350-400 nm) of a few μW/cm(2) intensity. The decay of the photoconducting state follows stretched exponential dynamics, which can be accelerated or slowed down on the application of gate voltage, thus imparting a novel functionality to the system.