2014/08/01 by Jun Cao, Lifa Zhang, Cao, Jun +7
Engineering · Physics and Astronomy · #Advanced Fiber Laser Technologies #FOS: Physical sciences #Optics (physics.optics) #Photonic and Optical Devices #Semiconductor Lasers and Optical Devices #physics.optics
paper · pdf · doi:10.48550/arxiv.1408.0148
4 pages, 5 figures, 26 references
arxiv created 2014/08/01 · openalex publication_date 2014/08/01 · arxiv updated 2014/08/04 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We design compact waveguide couplers via impedance-tunable transformation optics. By tuning impedance coefficients in the original space, two-dimensional metallic and dielectric waveguide couplers are designed with a high efficiency. Through tuning refractive index simultaneously, we find that the transformation medium inside a designed metallic waveguide coupler can be a reduced-parameter material for coupling waves between waveguides with arbitrary different cross sections and embedded media. In the design of dielectric waveguide couplers, we apply two different schemes: one is that both core region and its cladding region are contained in a transformed space, the other is only core region contained in the transformed space. The former has a very high efficiency near 100%; the latter is less efficient with a very small decline which can be a simplified candidate in the design of near-perfect dielectric waveguide couplers. The transformation medium for dielectric waveguide couplers can also be reduced-parameter material by selecting appropriate refractive index coefficients. Two-dimensional numerical simulations confirm our design with good performances.