Some aspects of the degradation of heterojunction lasers

The results are given of an experimental investigation of the catastrophic and slow degradation of heterojunction lasers. It is shown that the catastrophic failure occurs when the average density of the optical energy flux is (2–4)·10⁶ W/cm² and the local density is 10⁷ W/cm². Depending on this density, the service life of heterojunction lasers can range from several minutes to 100 h or longer: The catastrophic failure can be regarded as the extreme case of the slow degradation under the action of radiation. Heterojunction lasers emitting pulses of > 10 W power, 100 nsec duration, and 6 kHz repetition frequency can work for more than 100 h without suffering a large fall in the output power.