Q-switched operation of a 2.7 mu m cladding-pumped Er3+/Pr3+ codoped ZBLAN fibre laser

Abstract

We report a demonstration of Q-switched operation of a Er3+/Pr3+:ZBLAN fibre laser. Approximately an order of magnitude improvement in average power and pulse energy over previous results for Er3+-doped ZBLAN fibre lasers was achieved with no evidence of saturation in the output power due to amplified spontaneous emission (ASE) or excited state absorption (ESA). Pulse durations of 250 ns have been obtained and at a 19.5 kHz repetition rate a maximum average power of 19 mW has been achieved. The maximum power was limited by the speed of the mechanical Q-switch and it is likely that the overall performance of the system could be considerably by utilising a Q-switch based on an acousto-optic modulator. (C) 2004 Elsevier B.V. All rights reserved.