1.3 mu m resonant-cavity InGaAs/GaAs quantum dot light-emitting devices

Different types of microcavities for GaAs-based light emitting devices oper ating in the 1.3 mum spectral range are analysed. Microcavity light-emittin g diodes (MC LEDs) can be fabricated with different designs of distributed Bragg reflectors (DBRs), e.g.: top and bottom AlAs/GaAs semiconductor DBRs; bottom AlAs/GaAs semiconductor and top dielectric DBRs, and oxidized AlxOy /GaAs DBRs. MC LEDs operating in the 1.3 mum spectral range and characteriz ed by spectral width (13 nm) and narrow far-field pattern (< 20 degrees) ar e reported. In the case of vertical-cavity surface-emitting lasers (VCSELs) , practical implementation of injection lasing can be only achieved with ox idized AlxOy/GaAs DBRs, despite the fact that DBRs with nominally comparabl e parameters can be fabricated. It is shown that the 1.3 mum InAs/InGaAs qu antum dot (QD) VCSEL exhibits remarkably low internal losses, compared with QD VCSELs operating near 1 mum. This enables use of high-reflectance DBRs, important for lasing in low modal gain media, with high (> 40%) differenti al efficiency retained. A threshold current of <2 mA at 300 K is achieved ( lambda 1.304 mum).