title: Broadband unidirectional generation of surface plasmon polaritons with dielectric-film-coated asymmetric single-slit.
abstract: A dielectric-film-coated asymmetric single nanoslit is proposed to realize broadband unidirectional generation of surface plasmon polaritons (SPPs). Due to the tight field confinements by the dielectric film and the deep groove in the asymmetric single slit, the transmittance of the SPPs in the groove to the left side considerably decreases. This greatly suppresses the left-propagating SPP generation efficiency for a broad bandwidth. Meanwhile, the right-propagating SPP generation efficiency has a flat spectra range because of the low transmittance, too. So the unidirectional SPP generation with bandwidth of >100 nm around λ = 750 nm is experimentally achieved for the device lateral dimension of only 865 nm.
authors.affiliation: State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Chen
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Lei
authors.forename: Song
authors.initials: S
authors.lastname: Yue
authors.forename: Jinghua
authors.initials: J
authors.lastname: Xiao
authors.forename: Qihuang
authors.initials: Q
authors.lastname: Gong
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D008567:Membranes, Artificial; D012031:Refractometry / Q000295:instrumentation*; D012542:Scattering, Radiation; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
chemical_list: D008567:Membranes, Artificial