Modulated spontaneous and stimulated emission in luminescent films using one-dimensional photonic crystal filters

Abstract

One-dimensional photonic crystals (1DPCs) can effectively modulate the optical properties of embedded luminescent materials through defect state modes. An Optical filter is a passive 1DPC that has a defect state mode but no active light-emitting material. Contrary to the conventional approach of precisely placing a light-emitting defect layer within the interior of 1DPCs, this study explores the inquiry of whether the intrinsic defect mode of an optical filter can influence the spontaneous and stimulated emission properties of luminescent films when separating the defect layer from the luminescent layer. The findings reveal that, even when the luminescent film is positioned at the outermost layer with a weak localized electric field, the defect state mode can significantly enhance fluorescence emission intensity, narrows the emission linewidth, and accelerates the spontaneous emission transition rate of the luminescent film under normal incidence. Similarly, the defect state mode also can modify the amplified spontaneous emission (ASE) of the luminescent film, reduces ASE threshold and enhances ASE intensity. This approach not only improves the versatility and efficiency of luminescent modulation but also facilitates sample preparation, presenting a promising avenue for practical applications in optical devices and technologies.