Photonic crystal (PC) is a periodic arrangement of dielectric media, resulting in a complex band structure. Due to the periodic structure of PC, Bragg-like diffraction occurs and lights are prohibited to propagate within certain frequency range, called photonic band-gap (PBG). The both sides of PBG are called photonic band-edges (PBEs). One of the unique properties of PBE mode is that the photons at the PBE have zero group velocity inside the photonic crystal structure. Also, the lights at a PBE are distributed as standing waves in the structure with the electric field highly enhanced and confined within the particular medium in the structure.In this thesis, I introduce about enhanced phosphorescence from phosphor based on one-dimensional (1D) photonic crystal (PC) structure. Two kinds of polymer materials with different refractive indices are spin-coated alternately to fabricate 1D PC basis. CdSe/ZnS core-shell quantum dots (QDs) were embedded in the high index layer as the phosphorescence material. With the 1D PC phosphor structure design, the pump photon energy is tuned to the PBE of high-index band (HIB) so that the interaction between the pump photon and the QDs in the structure is enhanced. A reference phosphor structure that doesn’t appear PBG or PBE but does have similar photonic properties with bulk phosphor in the frequency range of interest is also designed and fabricated. Phosphorescence of 1D PC and reference phosphor structure is measured with changing of the pump wavelength across the PBE. Phosphorescence intensity reaches maximum when the pump wavelength corresponds to the PBE of 1D PC structure. It confirms that the experimental results have a good agreement with the theoretical prediction. Based on the measurement, we obtained that phosphorescence from the 1D PC phosphor is enhanced by the factor of 1.36 compared to that of the reference phosphor.
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