Nanophotonics VIII 2020, Virtual, Online, Fransa, 6 - 10 Nisan 2020, cilt.11345, (Tam Metin Bildiri)
In our work, transverse Anderson localization is introduced for the first time in a simple wedge-type optical waveguide, which is formed by a triangular air hole imbedded into a fused silica material via a conventional fiber drawing technique. The micro tube is filled with a polymeric medium consisting of fluorescent dye molecules and naturally formed air inclusions caused by the capillary effect to offer a scattering medium for photons to localize the interfered electromagnetic waves. Anderson localization is explored through various single modes at different emission wavelengths within the photoluminescence spectral bandwidth of dye molecules. The photonic design of the optical waveguide allows the guidance of a single Anderson localized mode and suppression of the other modes to enable investigation of the spontaneous emission rate of the emitters, which are principally coupled into a single Anderson localized mode. The physical mechanism behind the changes in the emission dynamics of the fluorescent emitters is investigated by the time-resolved spectroscopy, which is found to be on resonance dependent with a particular cavity mode. The fastest decay rate of the light emission from the excited dye molecules is attributed to be due to the photons that couple into the localized optical modes without any spectral detuning. The enhancement of the spontaneous emission rate by a factor of 2.2 is achieved as the majority of the photons are coupled into an Anderson localized mode. Thus, a simple wedge-type optical waveguide is demonstrated to provide an opportunity to enhance light-matter interaction and opens new avenues to understand the nature of the spontaneous emission dynamics of the fluorescent emitters that are trapped in quasi optical cavities.