1.3-μm InGaAsP planar buried heterostructure laser diodes with AllnAs electron stopper layer

This study reports on the realization of 1.3-mu m InGaAsP buried-heterostructure (BH) laser diodes (LDs) via an Fe-doped semi-insulating InP layer and an AllnAs electron stopper layer (ESL). Experimentally, the as-cleaved BH LD with an AllnAs ESL exhibited improved characteristics in terms of threshold current, slope efficiency, and maximum light output power at 90 C as compared to those of the normal BH LD without an AllnAs ESL In addition, high internal quantum efficiency or reduced threshold current density was observed, indicating increased modal gain in BH LDs fabricated with an AllnAs epilayer on top of the active region. It was also found that the temperature sensitivity of the BH LDs with an AllnAs ESL is more stable than that of the normal BH LDs. These results could be attributed to the suppression of thermal carrier leakage out of strain-compensated multiple-quantum-well by a large conduction-band offset of the AllnAs/InGaAsP heterojunction. Otherwise, without consideration of damping factor or coupling loss, the 3-dB bandwidth of the proposed BH LDs reaches a high value of 15.3 GHz. Finally, this TO-can packaged BH LD shows an eye-opening feature with the extinction ratio of 7.49 dB while operating at 10 Gbit/s at 50 mA. (C) 2011 Elsevier Ltd. All rights reserved.