title: Slanted gold mushroom array: a switchable bi/tridirectional surface plasmon polariton splitter.
abstract: Surface plasmon polaritons (SPPs) show great promise in providing an ultracompact platform for integrated photonic circuits. However, challenges remain in easily and efficiently coupling light into and subsequently routing SPPs. Here, we theoretically propose and experimentally demonstrate a switchable bi/tridirectional beam splitter which can simultaneously perform both tasks. The photonic device consists of a periodic array of slanted gold 'mushrooms' composed of angled dielectric pillars with gold caps extruding from a periodic array of perforations in a gold film. The unidirectional coupling results from the interference of the in-plane guided modes scattered by a pair of dislocated gold gratings, while the output channel is determined by the polarization of the incident beam. This device, in combination with dynamic polarization modulation techniques, has the potential to serve as a router or switch in plasmonic integrated circuits.
authors: State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China. jinchjun@mail.sysu.edu.cn and School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors: Yang
authors: Y
authors: Shen
authors: State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China. jinchjun@mail.sysu.edu.cn.
authors: Guisheng
authors: G
authors: Fang
authors: Department of Electrical Engineering, Ginzton Laboratory, Stanford University, Stanford, CA 94305-4088, USA. shanhui@stanford.edu.
authors: Alexander
authors: A
authors: Cerjan
authors: School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors: Zhenguo
authors: Z
authors: Chi
authors: Department of Electrical Engineering, Ginzton Laboratory, Stanford University, Stanford, CA 94305-4088, USA. shanhui@stanford.edu.
authors: Shanhui
authors: S
authors: Fan
authors: State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China. jinchjun@mail.sysu.edu.cn.
authors: Chongjun
authors: C
authors: Jin