Fibre-Format Photonic Source Based on Efficient Frequency Doubling of Continuous-Wave Erbium-Fibre Laser Amplifier

We demonstrate a compact photonic device based on efficient and wavelength-tunable doubling of an all fibre-format source. Quasi-phase-matched second-harmonic generation in periodically poled lithium niobate is used to generate 90.6mW at 775.9nm with a single-pass conversion efficiency of 14.7%. A tuning bandwidth of 2.1nm and a tuning temperature range of 150.6pm1.7°C can be achieved. The Er-doped seed fibre source is amplified by a clad-pumped Er³⁺/Yb³⁺-codoped fibre laser with a high output power up to 2.18W over a tunable wavelength range from 1535nm to 1570nm.