Vertical-Cavity Surface-Emitting Laser Diodes for Telecommunication Wavelengths

Abstract

A new approach for InP-based long-wavelength VCSELs based on buried tunnel junctions: the buried-tunnel-junction (BTJ) VCSEL is reviewed. Excellent cw laser performance has been demonstrated for BTJ-VCSELs in the 1.55μm wavelength range, such as sub-mA threshold currents, 0.9 V threshold voltage (at λ=1.55μm), operation voltages below 1.4V, 10-70 Ω series resistance, differential efficiencies >25%, up to more than 7mW optical output power, >100°C cw operation, stable polarization and single-mode operation with SSR of the order 50 dB. Also, recent achievements on high-speed long-wavelength VCSELs are reported.