Linear and nonlinear optical properties of one-dimensional photonic crystals containing ZnO defects

The linear and nonlinear optical properties of one-dimensional photonic crystals containing ZnO defects were studied by linear absorption spectroscopy and the femtosecond Z -scan technique. Photonic crystals containing ZnO defects, (Ta2 O5 SiO2) 5 ZnO (SiO2 Ta2 O5) 5, were prepared using electron-beam deposition and magnetron sputtering. The transmission spectra of these photonic crystals revealed a defect mode resonance and a broad photonic band gap. The observed transmission spectra could be described by applying the optical transfer matrix formalism to the multilayer structure. When compared with the Z -scan curve of the ZnO film, that of the resonant photonic crystal exhibited a larger transmittance dip. The enhancement of the nonlinear absorption in the resonant photonic crystal is due to the strong confinement of the optical field.