Laser action in periodically structured polymer films

ABSTRACT We present a study ofDistributed Feedback (DFB) Laser emission in various polymer materials. This permits efficient controlof the stimulated emission in dye doped polymer materials. Confinement and waveguiding effects are evidenced. We alsopropose a dynamical study ofthe effect using 4 wave mixing in the saturable absorption regime with stimulated emission.Keywords: organic device, polymer laser, distributed feedback, stimulated emission, degenerate four wave mixing. 1. INTRODUCTION Organic devices1 are built using technological tools which permit the patterning and micro-structuring of functional moleculesand polymers. For instance, a challenging issue in the field of designing molecular devices for photonic applications was toachieve a complete manipulation ofthe molecular order. In this respect, azo-dye aromatic polymers have been shown to offerinteresting properties for materials structuring using light matter interactions. Dual-frequency irradiation using appropriatecombinations of circular beam polarization have indeed been demonstrated to enable a full control of the molecular polarorder2'3. More recent results on photoinduced surface-relief gratings have also opened the way to molecular translationcontrol using optical fields4'5. A good understanding of the relevant parameters inherent to the molecular translationprocesses is still a key issue for the optimization of such opto-mechanical effect, but a simple microscopic model accounting