Ultrafast optical switching in Kerr nonlinear photonic crystals

ArticleinFrontiers of Physics in China 5(3):220-244 · September 2010with15 Reads
Impact Factor: 1.44 · DOI: 10.1007/s11467-010-0100-0

    Abstract

    Nonlinear photonic crystals made from polystyrene materials that have Kerr nonlinearity can exhibit ultrafast optical switching
    when the samples are pumped by ultrashort optical pulses with high intensity due to the change of the refractive index of
    polystyrene and subsequent shift of the band gap edge or defect state resonant frequency. Polystyrene has a large Kerr nonlinear
    susceptibility and almost instantaneous response to pump light, making it suitable for the realization of ultrafast optical
    switching with a response time as short as a few femtoseconds. In this paper, we review our experimental progress on the continual
    improvement of all-optical switching speed in two-dimensional and three-dimensional polystyrene nonlinear photonic crystals
    in the past years. Several relevant issues are discussed and analyzed, including different mechanisms for all-optical switching,
    preparation of nonlinear photonic crystal samples by means of microfabrication and self-assembly techniques, characterization
    of optical switching performance by means of femtosecond pump-probe technique, and different ways to lower the pump power
    of optical switching to facilitate practical applications in optical information processing. Finally, a brief summary and
    a perspective of future work are provided.

    Keywordsnonlinear photonic crystal-all-optical switching-Kerr nonlinearity-femtosecond pump-probe technique-photonic crystal cavities