Mode characteristics of vertical-cavity surface-emitting lasers based on GaAs quantum wells

The results of the detailed analysis of mode behavior of vertical-cavity surface-emitting lasers (VCSEL´s) with GaAs QW´s are presented. The design of the investigated VCSEL is similar to the design of commercial grade 850 nm VCSEL´s. The investigations of the laser mode structure have been carried out for VCSEL´s with apertures in the range from 1 μm up to 14 μm. The main lasing parameters have been calculated for the investigated VCSEL´s using 3D rigorous eigenmode expansion model. The measured value of the blue shift for the fundamental mode with the reduction of VCSEL´s aperture from 14 μm down to 1 μm is about 6 nm. The super-fine doublet and triplet structure of VCSEL´s modes has been discovered using a high resolution (∼10 pm) spectrometer. The presumable mechanisms of the observed mode splitting are presented in the report.