Well number, length, and temperature dependence of efficiency and loss in InGaAsP-InP compressively strained MQW ridge waveguide lasers at 1.3 mu m

Experimental measurements of external differential efficiency on 0.7% compressively strained multiquantum-well (MQW) ridge waveguide lasers operating at 1.3 mu m are presented. The lasers have the number of quantum wels (QW's) varying from 5 to 14 and cavity lengths ranging from 250 to 1000 mu m and were measured over a temperature range of -50 degrees C to 90 degrees C. A phenomenological model is introduced which shows that over a range of design and operating conditions, the behavior of the external differential quantum efficiency can be entirely explained by intervalence band absorption (IVBA). It is also shown that outside this range IVBA alone is slot sufficient to describe the behavior, indicating that current leakage becomes a significant factor, Ramifications of the IVBA contribution to the external differential quantum efficiency are investigated.