Spectral Narrowing of Photoluminescence in Conducting Polymer and Fluorescent Dyes Infiltrated in Photonic Crystal, Synthetic Opal

Abstract
Spectral narrowing of photoluminescence (PL) has been observed in conducting polymers such as poly(2,5-dialkoxy- p-phenylenevinylene) infiltrated in photonic crystals, synthetic opals, upon light excitation. Such spectral narrowing has also been observed in synthetic opals infiltrated with fluorescent dyes such as Rhodamine 6G and Coumarin. The threshold of the spectral narrowing in conducting polymers and dyes infiltrated in opal is much lower than that in their solutions. Dependence of spectral narrowing characteristics on the lattice periodicity of opals has also been studied. The results are discussed in terms of amplified spontaneous emission and lasing due to optical feedback in opal.