Bragg Extraction and Diffraction Properties of Active Organic/Inorganic 2D Dodecagonal Photonic Quasi-Crystals

摘要

We propose and experimentally demonstrate an active two-dimensional (2D) 12-fold photonic quasi crystal (PQC) which consists of air rods in a nanocomposite prepared by incorporating CdSe/CdS core/shell nanorods (NR) in a polymer. The effect of aperiodic order on the diffraction pattern was observed by measuring the far field diffraction pattern of the 2D-12 fold active PQC and investigated by analytical calculation of the theoretical Fourier spectrum. Light extraction has been found to occur via the band edge mode and to follow the dispersion properties of the dodecagonal structure. Finite-difference time-domain (FDTD) was used to calculate Bragg extracted light spectrum and compare the results of the numerical simulations with the experimental emission spectrum. The dispersion properties of the structure were also analyzed by theoretical band calculations and confirmed the presence of a resonance peak at 628 nm with a full width at half-maximum of 20 nm. Our results may provide useful tools for the design and optimization of novel photonic devices for light emitting applications.