Dynamically stable polarization characteristics of oxide-confinement vertical-cavity surface-emitting lasers grown on GaAs(311)A substrate

We experimentally demonstrated that the polarization mode of a VCSEL can be well controlled even under direct modulation by using the optical anisotropy of (n11)-oriented QWs. A schematic diagram is shown of a (311)A-oriented VCSEL with an oxide confinement structure. The epitaxial layer was grown on a GaAs(311)A substrate by molecular beam epitaxy. The active region consists of In/sub 0.2/Ga/sub 0.8/As double quantum wells centered in a single-wavelength-thick Al/sub 0.5/Ga/sub 0.5/As cavity. The upper and bottom DBR mirrors consist of a 25- and 22.5-pair AlAs/GaAs quarter-wave stack, respectively. A typical L-I characteristic is shown under continuous wave (CW) operation at 25/spl deg/C. The threshold current is 1.0 mA, and the lasing wavelength is around 990 nm.