Bimodal whispering-gallery mode lasing in micropillar cavity lasers

The results of the study of whispering-gallery mode splitting in lasers of the spectral range of 930–950 nm based on a vertical microcavity are presented. The use of non-absorbing distributed Bragg reflectors based on alternating Al$_{0.2}$Ga$_{0.8}$As/Al$_{0.9}$Ga$_{0.1}$As layers, made it possible to reduce the threshold optical pump power to 180 $\mu$W (for a 3 $\mu$m micropillar cavity laser). The bare quality factor for whispering-gallery modes exceeded 14000. A significant energy distance between the modes ($\sim$80 $\mu$eV), along with high stability of the lasing wavelength with increasing pump level ($\sim$220 $\mu$eV), indicates the prospects for using these lasers to modulate the polarization of radiation.