Degradation behavior of the active region and passive region in buried heterostructure (BH) distributed Bragg reflector (DBR) lasers

Changes in the threshold current and wavelength tuning characteristics due to the degradation of the active region and passive region in buried hetero structure (BH) distributed Bragg reflector (DBR) lasers are experimentally investigated. These changes are caused by the decrease in recombination car rier lifetime due to degradation. It is shown that the decrease in the carr ier lifetime is mainly accelerated as a result of increased carrier density . This suggests that the degradation of the active region depends more stro ngly on the threshold current density than on the operating current, On the other hand, the degradation of the passive region is related to the inject ed current density, which affects the stability of the wavelength tunabilit y of DBR lasers. (C) 1999 Elsevier Science Ltd. All rights reserved.