Single-mode tunable erbium:ytterbium fiber Fabry–Perot microlaser

Abstract
A compact tunable single-mode fiber laser at 1535 nm is developed by use of a novel combination of high-gain erbium:ytterbium (Er:Yb) phosphate-glass fiber within a fiber Fabry–Perot cavity. We demonstrate what we believe to be the shortest Er:Yb phosphate-glass fiber Fabry–Perot laser ever reported, having a 100-μm cavity length and a continuous wavelength tuning range over 4.52 nm (limited by the sharp fiber gain peak). An alternative three-mirror laser design has also demonstrated single-mode lasing operation.