Time Discrimination in Solid-State Infrared Quantum Counters

Abstract

The paper discusses various considerations in the practical realization of the infrared solid-state quantum counter recently proposed by Bloembergen. It is suggested that a high degree of discrimination between the quantum to be counted, and the optical pumping flux, could be attained by a time-sequence switching system; it is estimated that an isolation of ∼160 db might be required. The proposal demands that at least one of the levels in the crystal have a long lifetime, and a simple expression is derived for the overall efficiency of the detector in this case. An additional gain in efficiency and isolation would result if ``double pumping'' were used, with detection in the ultraviolet. In conclusion a suggested layout of components is presented incorporating the switching scheme discussed herein.