Multimode Suppression of a Vertical-Cavity Surface-Emitting Laser by a Single-Mode Fiber Cavity

This work presents a simple method to conduct a single-transverse-mode output in a commercial multimode vertical-cavity surface-emitting laser by a single-mode fiber cavity (SMFC). A stable fundamental-mode lasing was achieved within a tuning range as wide as 1000 GHz, or 2.6 nm, with a sidemode suppression ratio of around 20 dB. The success of the SMFC was attributed to a multimode suppression mechanism. The simplicity of the experimental setup makes the SMFC more feasible in many practical applications.