Spectra and thresholds of the whispering-gallery modes in microdisk laser with radially non-uniform gain area

Quasi-3D analysis of lasing spectra and thresholds of microdisk lasers with radially non-uniform gain is presented. This analysis is based on the approximate reduction of a 3D problem for a finite thickness disk to a 2D one, with the effective index method. The new point is the full account of the effective index dispersion. The 2D study is based on the set of the Maxwell equations with transmission conditions at the disk boundaries and radiation condition at infinity.