Single polarisation fibre lasers using an integral polariser

Fibre lasers represent a new class of active fibre devices with considerable potential for use in telecommunications, sensors and laboratory measurements. For these applications the realisation of a practical single-polarisation single-mode (SPSM) fibre laser is of considerable interest. In this paper we report an integral fibre polariser technique for making SPSM fibre lasers. The corresponding theory, design method and experimental results are also presented. It is shown that it is far more efficient to use an intra-cavity polariser than to polarise the output light with an external polariser