Increased radiation hardness of GaAs laser diodes at high current densities

摘要

Total light output of GaAs laser diodes has been measured at 300 and 76deg;K before and after successive neutron irradiations to a cumulative fluence of 6.5times;1014neutronsol;cm2( 10 keV). The range of current densities used extended from well below the laser threshold current density to the maximum allowable value. Both the subthreshold light output and the threshold current density were sensitive to neutron damage in agreement with previous observations. However, at current densities significantly above threshold the light output is much less sensitive to irradiation and, in fact, the light output at 76deg;K was observed to increase following irradiation. These latter results have significant practical importance for cases in which laser diodes must operate in a radiation environment.