Photonic-crystal laser mediated by polaritons

A polariton-mediated photonic-crystal laser is proposed, which has a period ic structure containing excitonic and gain materials in its unit cell. This type of structure is shown to significantly intensify optical gain near th e polaritonic band edge as a result of using a light, the band of which is split into small polaritonic bands by exciton-photon coupling. Consequently , this laser exhibits much lower threshold gain than those of other lasers studied here and it oscillates in the single mode because of its strong mod e selectivity. These advantages stem from the photon field modulated extrem ely by adding excitons to conventional photonic crystals.