Proposal and experiment of a novel Er‐doped fiber‐ring laser to suppress mode instability induced by polarization fluctuation

A novel Er‐doped fiber‐ring laser having less mode instability due to polarization fluctuation is proposed and experimentally investigated. The Er‐doped fiber is twisted to form a fiber‐ring laser. The right‐hand‐ and the left‐hand‐rotated circular waves preserved in the twisted fiber are exchanged by a fiber type ½ element placed in the fiber ring. This configuration can fix the separation between two polarization resonances (i.e., two ESOPs' resonances) and suppress the polarization‐mode instability. Both theory and experiment are presented conducted; the experiment his confirmed our design. In addition, the temperature effects on this fiber‐ring laser have been measured © 1995 John Wiley & Sons. Inc.