Effects of Neutron Radiation on Aluminum-Gallium-Arsenide Lasers.

摘要

Double heterojunction aluminum-gallium-arsenide laser diodes were irradiated in a nuclear reactor to determine the effects of neutron radiation. Two types of lasers were used; both types of diodes showed significant decreases in power output at neutron fluences of 10 to the 14th power n/sq cm. Linear increases in threshold current and linear decreases in external quantum efficiency were observed. There was no significant change in bias voltage versus forward current or in the spectral composition of the output of the diodes at neutron fluences up to 10 to the 15th power n/sq cm. Formulas were developed to predict the changes in threshold current, external quantum efficiency and power at a constant current above threshold. Damage coefficients for these formulas were derived from the irradiation data. Unusual discontinuities were observed in the poewr output versus input current curves of some diodes. Neutron irradiation tended to enhance these anomalies.