Influence of ordering on the polarization characteristics of GaInP Vertical-Cavity Surface-Emitting Lasers
- Y. H. Chen, C. I. Wilkinson, J. Woodhead, J.P.R David, C. C. Button, P. N. Robson
- IEEE Photon. Technol. Lett.,
Polarisation control is demonstrated in circular gainguided top-surface emitting vertical cavity lasers by etching a narrow trench near the cavity aperture. An optimum etch depth exists for which all modes are pinned in a single polarisation. The etch orientation determines the dominant polarisation state of emission by modifying the spontaneous emission coupling into each polarisation state. Polarisation control is also enhanced by modifying the device strain. These effects are sufficient to pin the polarisation in monomode and multimode devices and extinction ratios of greater than 50 may be achieved over the device bias current operating range.