title: Ultracompact photonic crystal polarization beam splitter based on multimode interference.
abstract: We propose a theoretical design for a compact photonic crystal (PC) polarization beam splitter (PBS) based on the multimode interference (MMI) effect. The size of a conventional MMI device designed by the self-imaging principle is not compact enough; therefore, we design a compact PC PBS based on the difference of the interference effect between TE and TM modes. Within the MMI coupler, the dependence of interference of modes on propagation distance is weak for a TE wave and strong for a TM wave; as a result, the length of the MMI section can be only seven lattice constants. Simulation results show that the insertion losses are 0.32 and 0.89 dB, and the extinction ratios are 14.4 and 17.5 dB for Port 1 (TE mode) and Port 2 (TM mode), respectively.
authors.affiliation: Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, 1001 Da Hsueh Road, Hsinchu 30010, Taiwan. mflu@must.edu.tw
authors.forename: Ming-Feng
authors.initials: MF
authors.lastname: Lu
authors.forename: Shan-Mei
authors.initials: SM
authors.lastname: Liao
authors.forename: Yang-Tung
authors.initials: YT
authors.lastname: Huang
mesh_terms: D055096:Optical Devices; D017785:Photons; D012031:Refractometry / Q000379:methods*