Coupling of Defect Modes in Cholesteric Liquid Crystals Separated by Isotropic Polymeric Layers

Shaohua Gao; Yanzi Zhai; Xinzheng Zhang; Xiao Song; Jiayi Wang; Irena Drevensek-Olenik; Romano A Rupp; Jingjun Xu

doi:10.3390/polym10070805

Coupling of Defect Modes in Cholesteric Liquid Crystals Separated by Isotropic Polymeric Layers

Polymers (Basel). 2018 Jul 23;10(7):805. doi: 10.3390/polym10070805.

Authors

Shaohua Gao¹, Yanzi Zhai², Xinzheng Zhang³, Xiao Song⁴, Jiayi Wang⁵, Irena Drevensek-Olenik⁶, Romano A Rupp^{7

8}, Jingjun Xu^{9

10}

Affiliations

¹ The MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics and School of Physics, Nankai University, Tianjin 300457, China. gaosh@mail.nankai.edu.cn.
² The MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics and School of Physics, Nankai University, Tianjin 300457, China. yanzizhai@mail.nankai.edu.cn.
³ The MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics and School of Physics, Nankai University, Tianjin 300457, China. zxz@nankai.edu.cn.
⁴ The MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics and School of Physics, Nankai University, Tianjin 300457, China. 2120170195@mail.nankai.edu.cn.
⁵ The MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics and School of Physics, Nankai University, Tianjin 300457, China. 2120170196@mail.nankai.edu.cn.
⁶ Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19 and Department of Complex Matter, J. Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia. irena.drevensek@ijs.si.
⁷ The MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics and School of Physics, Nankai University, Tianjin 300457, China. romano.rupp@univie.ac.at.
⁸ Faculty of Physics, Vienna University, Boltzmanngasse 5, A-1090 Wien, Austria. romano.rupp@univie.ac.at.
⁹ The MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Institute of Applied Physics and School of Physics, Nankai University, Tianjin 300457, China. jjxu@nankai.edu.cn.
¹⁰ Synergetic Innovation Center of Chemical Science and Engineering, Tianjin 300071, China. jjxu@nankai.edu.cn.

Abstract

Cholesteric liquid crystal structures with multiple isotropic defect layers exhibit localized optical modes (defect modes). Coupling effects between these modes were simulated using the finite difference time domain method. Analogous to the well-known result of the tight-binding approximation in solid state physics, splitting of the defect modes takes place, as soon as the structure contains more than one defect layer. The dispersion relation of the mini-bands forming within the photonic band gap of the structure is calculated numerically. The structures might have promising applications for multiwavelength filters and low-threshold lasers.

Keywords: cholesteric liquid crystals; mode coupling; optical defect modes; photonic density of state.

Abstract

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