title: Bidirectional surface wave splitter at visible frequencies.
abstract: We experimentally demonstrate a metal-film bidirectional surface wave splitter for guiding light at two visible wavelengths in opposite directions. Two nanoscale gratings were patterned on opposite sides of a subwavelength slit. The metallic surface grating structures were tailored geometrically to have different plasmonic bandgaps, enabling each grating to guide light of one wavelength and prohibit propagation at the other wavelength. The locations of the bandgaps were experimentally confirmed by interferometric measurements. Based on these design principles, a green-red bidirectional surface wave splitter is demonstrated, and the observed optical properties are shown to agree with theoretical predictions.
authors.affiliation: Center for Optical Technologies, Electrical and Computer Engineering Department, Lehigh University, Bethlehem, Pennsylvania 18015, USA. qig206@lehigh.edu
authors.forename: Qiaoqiang
authors.initials: Q
authors.lastname: Gan
authors.forename: Filbert J
authors.initials: FJ
authors.lastname: Bartoli