title: Modeling of evanescent coupling between two parallel optical nanowires.
abstract: Evanescent coupling between two parallel nanowires is investigated using the finite-difference time-domain method. Silica, tellurite, and silicon nanowires are used as typical materials in the simulation. Compared with weakly coupled waveguides, strongly coupled nanowires show much smaller transfer lengths without sacrificing high coupling efficiencies, suggesting possibilities for developing highly compact evanescent-coupling-based nanowire photonic devices, as well as for achieving high-efficiency interconnection between nanowires and external optical systems. Meanwhile, the polarization-dependent coupling properties, the considerably high minimum coupling efficiency, and the supermode-cutoff-like behavior are also observed. Evanescent coupling properties of strongly coupled nanowires demonstrated may provide valuable references for practical applications of optical nanowires.
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, Department of Optical Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Keji
authors.initials: K
authors.lastname: Huang
authors.forename: Shuangyang
authors.initials: S
authors.lastname: Yang
authors.forename: Limin
authors.initials: L
authors.lastname: Tong