V-groove side-pumped 1.5 µm fibre amplifier

A side-pumping technique, using an imbedded v-groove is used to efficiently pump a double-clad Er/Yb doped fibre amplifier operating at 1.5 µm and pumped at 0.98 µm. A diode-to-fibre coupling efficiency of 76% was measured for a 100 µm wide broad stripe laser diode and a fibre with a 50 × 120 µm first cladding. A maximum output power of 185 mW, and separately, a small signal gain of 35 dB, are demonstrated.