Theoretical study of a classically confined solid-state photomultiplier

A detailed theoretical analysis is presented of the workings of a new solid-state photomultiplier whose gain is derived through impact excitation events of classically confined electrons out of thin semiconductor layers. The highly doped layers containing the target or ionizing electrons are made sufficiently wide so as to avoid spatial quantization effects. The primary difference of this scheme is due to the different k vector conservation requirement implicit in confined quantum state devices. The calculations presented serve as a lower bound on the gain of a confined electron state photomultiplier. However, owing to the classical confinement, the dark currents, due to both thermionic emission and tunneling, are substantially lower, by several orders of magnitude, than that in a quantum confined device. Calculations of the ionization probability, average ionization rate, gain, dark current, and mean thermalization distance are presented