Room-temperature operation of index-guided 1.55 /spl mu/m InP-based vertical-cavity surface-emitting laser

A novel concept for long-wavelength InP-based vertical cavity lasers (VCSELs) with a buried tunnel junction enables effective electrical and optical confinement and yields low series resistance. VCSELs with aperture diameters of 13 /spl mu/m exhibit threshold currents of 10 mA, single-mode emission, a quantum efficiency of 10% and a threshold voltage of only 1.2 V.