Electrical conductivity of TiO2 thin film on insulator induced by radiation exposure

We investigate the electrical conductivity of a TiO2 surface layer on insulators induced by radiation exposure. The surface layer is sufficiently thin to transmit radiation (typically gamma-rays) without absorption, but exhibits a current signal indicating the interaction processes of the radiation with substrate insulators. We explain this effect arising from the layered structure and demonstrate a Monte Carlo simulation of photons and electrons to show that electrons generated by irradiation in the substrate travel and cause energy deposition onto the thin layer, envisaging a new type of radiation detector.