On the design of a Nd3+ doped silica fiber-laser using a cholesteric liquid crystal mirror

We report operation of a Nd3+-doped fiber-laser using a cholesteric liquid crystal acting as a narrow band reflector. The aim of this work is to apply to a fiber-laser the particular optical properties of an helical structure , whatever is the medium exhibiting this structure, either a liquid crystal or either any other material. The advantage of the use of these mediums in the design of fiber-lasers is that they can favourably take the place, in an easy and compact way, of several optical elements such as a polarizer an d a quarter-wave plate at one and the same time. This technology promises t o design rugged compact low cost tunable coherent sources the lasing range of which can easily be adjusted. We emphasize here the particular part play ed by the cholesteric liquid crystal-glass interface in the laser action of the fiber.