Shape dependence of emission from microdisk lasers

The emission characteristics of GaAs Whispering Gallery microdisk lasers have been investigated for different disk shapes and sizes. Elliptical structures showed a substantial increase in the emission intensity from the sides of the disk with the greatest curvature, while stadium-shaped disks did not support any laser emission. Deformation of circular disks towards squares reduces the number of resonant modes for lasing but does not eliminate lasing totally; thus operation with non-Whispering-Gallery modes is possible, and this implies that such operation may be relevant even for circularly symmetrical lasers.