Er. Hegblom et al., ESTIMATION OF SCATTERING LOSSES IN DIELECTRICALLY APERTURED VERTICAL-CAVITY LASERS, Applied physics letters, 68(13), 1996, pp. 1757-1759
Dielectric apertures, formed by oxidation or wet-etching of high Al co
ntent AlGaAs layers in vertical cavity lasers, have recently been used
for improved device performance. In this letter an iterative numerica
l analysis is used to estimate the excess optical losses as the device
diameter is reduced. For smaller sizes, where single-mode devices are
possible, the optical scattering losses become significant unless the
aperture is tapered to approximate a perfect lens or is thin to appro
ximate a weaker waveguide. (C) 1996 American Institute of Physics.