Polarization stabilization in vertical-cavity surface-emitting lasers through asymmetric current injection

We present experimental evidence that asymmetric current injection in intracavity contacted vertical-cavity surface-emitting lasers (VCSELs) stabilizes the polarization of the emitted light. Anisotropies in the gain and loss mechanisms introduced by asymmetric current injection are considered to explain this effect. The design scheme opens perspectives to obtain actual polarization control in VCSEL

Asymmetric current injection for polarization stabilization in vertical cavity surface emitting lasers

Intra-cavity contacted In/sub 0.17/Ga/sub 0.83/As/AlAs VCSELs with asymmetrical and symmetric contacts were fabricated and characterized. The square devices with asymmetric current injection emit light polarized perpendicular to the direction of the current injection, despite the fact that these VCSELs have higher order transverse modes. The asymmetric current injection scheme seems thus to be able to stabilize the polarization. We expect that smaller devices working in single mode operation will further enhance the polarization contrast