Vertical cavity surface emitting lasers utilizing native oxide mirrors and buried tunnel contact junctions

Vertical cavity surface emitting lasers (VCSELs) are demonstrated with high-index-contrast native-oxide-based (AlxOy) distributed Bragg reflectors (DBRs) on both sides of a “2λ” cavity, thus creating a compact (thin, ∼2.8 μm) laser structure. Selective oxidation of high Al composition AlxGa1−xAs layers yields a structure with a four period upper AlxOy/GaAs DBR, a 5.5 period lower AlxOy/GaAs DBR, and a buried oxide current aperture. A reverse-biased tunnel contact junction provides hole injection via lateral electron current between the upper DBR and the oxide aperture layer. These VCSELs operate with submilliampere thresholds, high spontaneous efficiencies, and excellent polarization control.