Inhibited/enhanced fluorescence of embedded fluorescent defects by manipulation of spontaneous emission based on photonic stopband

Abstract

Inhibition and enhancement of the fluorescence from embedded fluorescent defects in colloidal crystals (CCs) is demonstrated. The embedded defects, which are verified by the passbands and scanning electron microscope images, are fabricated inside the CCs by employing two-photon polymerization of allyl-fluorescein (allyl-FL) doped photoresist. The fluorescence image is indistinct when the photoluminescence band of allyl-FL locates at the photonic stopband. However, a bright fluorescence image is observed when the photoluminescence band is located at the photonic stopband edge. The inhibition and enhancement in fluorescence is ascribed to the manipulation of the spontaneous emission of the allyl-FL by the photonic stopband, which is verified by the fluorescence spectra of the allyl-FL infiltrated in the CCs with different photonic stopbands. This study will be prospective in bio-imaging and miniature lasers.