Search

We have demonstrated the realization of a plasmonic random polymer fiber laser (RPFL) based on gold nanoparticles (NPs) doped one-dimensional disordered gain polymer optical fiber (POF). In this work, the plasmonic RPFL is fabricated by directly drawing from a laser dye and gold NPs system codoped POF. The random lasing can be obtained from the waveguide-plasmon-scattering in the POF system. Meanwhile, the dye doped fiber in the presence gold NPs has high photostability.

We have reported the realization of a plasmonic random fiber laser based on the localized surface plasmonic resonance of gold nanoparticles (NPs) in the liquid core optical fiber. The liquid core material contains a dispersive solution of gold NPs and laser dye pyrromethene 597 in toluene. It was experimentally proved that the fluorescence quenching of the dye is restrained in the optical fiber, which is considered one of the main sources of loss in the traditional laser system. Meanwhile, the random lasing can be more easily obtained in the random laser system with more overlap between the plasmonic resonance of the gold NPs and the photoluminescence spectrum of the dye molecules.

In this work, the self-collimating phenomenon in two-dimensional rhombic-lattice photonic crystals is discussed in detail. The equi-frequency contours of a rhombic-lattice rod-type photonic crystal structure are calculated with the plane wave expansion method for different lattice angles and rod radii. A broad range of flat and open equi-frequency contours is found. A rhombic-lattice photonic crystal made of 301???21 silicon rods (n?=?3.5) in air is presented as an illustration to demonstrate the broadband all-angle self-collimation. The bandwidth for all-angle self-collimation is verified to be 17.42% of the central frequency by simulations based on the finite-difference time-domain method. The all-angle self-collimation is found to be polarization-independent and the frequency for simultaneous TM and TE all-angle self-collimation is identified and verified by finite-difference time-domain simulations.

A type of Christiansen filter that takes the form of a cylindrical lens is proposed. This kind of Christiansen filter has a pass band narrower than the traditional one, with more means of control of its performance; it could approximate arbitrary functions over a frequency range of interest. An inverse scattering theory for the synthesis of such a filter is developed and a systematic design technique is established. A desired, prescribed response can be tailored by properly configuring the lens of the filter. A Gaussian filter centered at 225 nm with a full width at half maximum of 1 nm is synthesized and is numerically modeled on a computer using the finite difference beam propagation method. The simulation results confirm the feasibility of the proposed Christiansen filter.