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Rejection of Fluorescence Background in Resonance and Spontaneous Raman Microspectroscopy
Published on: May 18, 2011
Nondegenerate two-beam coupling in Kerr nonlinear photonic crystals
1Department of Physics and Institute of Nano Science and Technology (INST), The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Abstract:
We show that the energy-transfer efficiency by nondegenerate two-beam coupling in a one-dimensional Kerr-nonlinear superlattice can be enhanced by several orders of magnitude as compared with that in a homogeneous medium of the same nonlinearity and length. This significant enhancement utilizes the strong localized field at the band-edge state, two-frequency localized state, or defect state. Due to the intensity-induced index modulation, the bistability is observed, and because of the energy transfer between different wavelength components, the tristability behavior is induced.
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