Charge Deposition, Photoconduction, and Replacement Current in Irradiated Multilayer Structures

The electronic effects on an irradiated one dimensional dielectric-metal slab structure have been modeled. The effects considered include: radiation driven currents, charge deposition, applied electric fields, deposited charge fields, field driven conductivity currents and radiation induced photoconductivity. The time and spatial dependence of the electric current density, charge density and electric field are determined. The time dependence of the replacement current flowing between metal slabs is calculated. Results are given for x-rays of energies from 30 to 1250 keV. Interesting results predict electric fields > 106 V/cm, time varying replacement currents which even reverse sign, and multipole electric fields in one dimension. Experimental measurements produce time dependent replacement currents under 60Co irradiation.