Single-Longitudinal-Mode Erbium-Doped Fiber Ring Laser Based on High Finesse Fiber Bragg Grating Fabry–PÉrot Etalon

TLDR

The paper introduces a simple, stable single‑longitudinal‑mode erbium‑doped fiber laser. The laser uses an apodized fiber Bragg grating and a high‑finesse FBG‑based Fabry‑Perot etalon in a ring cavity, where the FBG selects modes and the etalon provides a narrowband filter for efficient SLM operation. The device achieves a stable single‑longitudinal‑mode output at 1.55 µm with a 2.5 kHz linewidth and allows continuous 8 nm wavelength tuning via strain on the FBG and etalon.

Abstract

We present a simple and stable single-longitudinal-mode (SLM) erbium-doped fiber laser. It consists of an apodized fiber Bragg grating (FBG) and a high finesse FBG-based Fabry-Perot (FP) etalon in the ring cavity. The apodized FBG acts as a wavelength discriminative component selecting a few oscillation modes while the FP etalon serves as narrow bandwidth bandpass filter to further discriminate and select SLM efficiently. Stable SLM laser output at 1.55 m with linewidth about 2.5 kHz is acquired. Furthermore, continuous wavelength tuning over 8 nm is achieved by simultaneously applying strain to the FBG and the FP etalon.