Characterization of the optical gain in doped polymer optical fibres

Abstract The properties of the amplified spontaneous emission in rhodamine-6G doped graded-index polymer optical fibres of two different dopant concentrations have been analyzed by using the Variable Stripe Length method, both theoretically and experimentally. A theoretical model based on the laser rate equations describes the dependence of the emitted spectrum on the pumped length successfully. The fibre gains and their dependence on the dopant concentration have been analyzed.