The effect of intracavity apertures and distributed Bragg reflectors (DBRs) on transverse-mode discrimination in vertical-cavity surface-emitting lasers is investigated theoretically. The effects of aperture shape and size as well as the stop-band width of the DBRs are examined with the goal of optimizing the mode discrimination for better lasing stability and higher single-mode power. It is found that decreasing the width of the DBRs' stop band, by means of controlling the material composition and number of layer pairs, increases significantly the optimum aperture size and hence the single-mode output power.
- DBR mirrors
- Optical design