All-optical controlled multifunction operation in two-dimensional photonic crystals

We present experimental results which demonstrate that, under different external optical stimulus, a single two-dimensional photonic crystal can provide different all-optical functions. We demonstrate four of these functions: spectral tuning of the photonic band gap, very fast switching operation, amplification and laser emission. These effects are achieved via optically-injected carriers induced nonlinear response of the photonic crystal. We believe that our experimental results constitute the first step towards the design of versatile multifunctional devices where optical response can be reconfigured via nonlinear interactions.