Loss limitations in dielectrically apertured vertical cavity lasers

Summary form only given. Researchers have made significant improvements in vertical-cavity lasers (VCLs) by use of thin apertures that confine the current and the optical mode. It is believed that the apertures provide lateral waveguiding with lower scattering losses than the sidewalls of the etched mesa index waveguides. However, because the apertures are discrete intracavity elements, there will be some associated optical scattering unless the lateral index profile of the aperture is that of a perfect lens (i.e. parabolic). To quantify these round-trip modal losses, we use a one-dimensional (l-D) propagation model like the classical "Fox-Li" approach, in which a scalar field is propagated around a cavity until the field does not change from one pass to the next. We account for the full angular reflection spectrum of the DBRs and use the equivalent distributed index to account for the position of the aperture relative to the standing wave intensity profile in the cavity.