1.3-μm InP-based quantum-well lasers with n-doped separate confinement heterostructure layers for high-temperature operation

We present a novel approach for reducing the light output power penalty in 1.3-μm InP-based strained-layer (SL) MQW lasers at elevated temperatures. It is shown that n-type doping in the separate confinement heterostructure (SCH) layers increases the barrier height in the valence band profiles effectively, which makes it possible to suppress the pile-up of holes in the SCH region under high-temperature, high-injection conditions. One significant impact of this approach is that the power penalty can be reduced to one half of that in conventional SL-MQW lasers with undoped SCH. We show that SL-MQW structures with n-doped SCH have a great potential for realizing a low power penalty as well as high efficiency in InP-based MQW lasers at elevated temperatures.