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

Abstract
Different types of microcavities for GaAs-based light emitting devices operating in the 1.3 µm spectral range are analysed. Microcavity light-emitting 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 µm spectral range and characterized by spectral width (13 nm) and narrow far-field pattern (xOy/GaAs DBRs, despite the fact that DBRs with nominally comparable parameters can be fabricated. It is shown that the 1.3 µm InAs/InGaAs quantum dot (QD) VCSEL exhibits remarkably low internal losses, compared with QD VCSELs operating near 1 µm. This enables use of high-reflectance DBRs, important for lasing in low modal gain media, with high (>40%) differential efficiency retained. A threshold current of <2 mA at 300 K is achieved (λ = 1.304 µm).