Neutron effects in high-power GaAs laser diodes

The radiation response of broad-area GaAs quantum-well laser diodes and arrays that emit up to 2 W from a 100-μm to 150-μm region at the front facet was tested. Results at neutron fluence levels up to 10¹⁵ n/cm² are reported. The lasing threshold currents of these high-power GaAs laser diodes and arrays increased less than 40% after exposure to 10¹⁴ n/cm² . Threshold current rose by 100% to 250%, and a possible increased susceptibility to facet damage was observed at 10¹⁵ n/cm². The results indicate that the mechanisms for degradation are the same as those observed for the older semiconductor laser technologies