Wavelength-tunable single-frequency and single-polarisation er-doped fibre ring-laser with 1.4 kHz linewidth

Abstract

A narrow linewidth of 1.4 kHz with single frequency operation is demonstrated in an Er-doped fibre ring-laser. A stable lasing spectrum can be achieved using a single polarisation fibre-cavity. An optical bandpass filter incorporated in the ring-cavity makes the lasing wavelength tunable, and a 2.8 nm tuning range is demonstrated.