Optically and Electrically Pumped of Ga0.65In0.35N0.02 As0.98/GaAs Vertical-Cavity Surface-Emitting Lasers (VCSELs) for 1.3 μm Wavelength Operation

The 1.27 mu m pulsed operation of an electrically and an optically pumped simple bar Ga0.65In0.35N0.02As0.98 vertical-cavity surface-emitting laser (VCSEL) is reported. VCSELs are becoming an increasingly important optical source technology for long haul fibre communication systems, and are essentially working above a threshold. The structure of the device employs 21 pairs of undoped top mirrors to provide above 99 % reflectivity, while the bottom mirrors have 24 pairs of n-doped resulting in over 99.9 % reflectivity. The device has undoped top distributed Bragg reflectors (DBRs). Therefore, problems such as those associated with the refractive index contrast and the current injection, which are common with doped DBRs in conventional VCSELs, are avoided. Their intrinsic active region consists of a 7 nm Ga0.65In0.35N0.02As0.98 quantum wells QWs that embedded in undoped GaAs. At room temperature, the device was characterised through L-V and by spectral photoluminescence PL measurements. Theoretically, a peak gain at around 1.2 dB is obtained for 1.27 mu m wavelength range.