Compact super-Gaussian evanescent beam expanders for integrated photonics

Abstract

This paper presents the modeling, design and experimental validation of integrated optical super-Gaussian evanescent beam expanders. A general analytical model for converting the mode of a single mode waveguide into a wide super-Gaussian slab mode is derived and the design procedure is described. Several structures have been experimentally verified on wafer scale and the results are in good correspondence with the design. Applications where wide flat-top beams would prove their superiority are, for instance, bio-sensing applications, flow cytometry and on-chip microscopy.