Investigation of operational characteristics and possibility of obtaining highly detuned GaInNAsSb VCSEL

Abstract

Comprehensive computer simulation was used to investigate a possibility to highly detune GaInNAsSb VCSEL devices from the wavelength of 1422 nm, corresponding to the highest RT optical gain of their Ga0.62In0.38N0.023As0.95Sb0.027/GaN0.025As0.975 quantum‐well (QW) active regions, to 1500 nm, closer to the wavelength used in the third generation of the fibre optical communication. The RT continuous‐wave (CW) lasing operation of the 1500‐nm VCSEL, with an identical active region to that of the 1422‐nm one and the cavity properly re‐designed for the 1500‐nm wavelength, may be obtained for the active‐region temperature increased by about 94 K over RT which is necessary for a required QW gain shift to longer wavelengths. However, such a temperature‐induced CW RT VCSEL lasing operation at 1500 nm is reached at the expense of an increase in its threshold current density by as much as 10 times as compared to that of the 1422‐nm VCSEL. Detuned devices has different operational characteristics e.g. worse mode selectivity and threshold current decrease with ambient temperature either quantum‐wells number increase. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)