Periodic metal-dielectric interfaces for photonic applications

The photonic bandgap properties of periodic interfaces between noble metals and dielectrics exhibiting third-order optical nonlinearity are investigated. Some device configurations aimed at obtaining all-optical switching around 1500 nm are proposed, based either on the excitation of propagating surface plasmons at a sinusoidally modulated interface or on the back-reflection properties of a sawtooth-modulated metal-dielectric interface under normal incidence of the radiation. In the second case, 35% switching of 15-ps 5-nJ input pulses can be obtained using polydiacetylenes as the nonlinear dielectric.