Enhanced photovoltage in perovskite-type artificial superlattices on Si substrates

We have fabricated a three-component perovskite-type superlattice (SL) consisting of La(0.9)Sr(0.1)MnO(3), SrTiO(3) and LaAlO(3) with atomic scale control by laser molecular beam epitaxy on Si substrates. When a He-Ne laser irradiated the superlattice by side illumination, a stable photovoltage was produced and the responsivity reached 46.7 mV mW(-1) which is six times higher than that of a similarly grown La(0.9)Sr(0.1)MnO(3) single layer on Si substrates. This work demonstrates the potential of the present SL in photo-detectors operating at room temperature.