Increasing the coupling efficiency of a microdisk laser to waveguides by using spiral structures

Abstract

In this article, we show that the introduction of a spiral waveguide to a GaAs microdisk that works both as a waveguide and circular Bragg reflector can improve coupling efficiency to almost 90%. The same structure with the addition of a taper can couple up to 80% of the gener ated power into a slot waveguide.