Wang Tzyy-Jiann, Yang Shun-Chen, Chen Tien-Jung, Chen Bo-Yu
Institute of Electro-Optical Engineering, National Taipei University of Technology, Taipei 10608, Taiwan.
Opt Express. 2012 Jul 2;20(14):15853-8. doi: 10.1364/OE.20.015853.
We present wide electrical tuning of microring resonators with auto-realigned nematic liquid crystal (NLC) cladding. By applying electric field, homeotropically-aligned negative Δε NLC with non-rubbed alignment layers is auto-realigned along the microring waveguide due to the protruding of the ridge structure. The consistent cladding index distribution along the microring waveguide produces effective tuning of the resonant wavelength. It achieves a large tuning range of 13nm for TM mode and 2.1nm for TE mode. The NLC reorientation characteristics are investigated by minimizing Oseen-Frank energy. The proposed microring resonator owns the features of large tuning range and bi-polarization wavelength tuning.
我们展示了采用自动重新排列向列型液晶（NLC）包层的微环谐振器的宽电调谐特性。通过施加电场，具有非摩擦取向层的垂直排列负介电常数向列型液晶由于脊结构的突出而沿微环波导自动重新排列。沿微环波导一致的包层折射率分布实现了谐振波长的有效调谐。对于TM模式，实现了13nm的大调谐范围，对于TE模式，实现了2.1nm的大调谐范围。通过最小化奥森 - 弗兰克能量来研究向列型液晶的重新取向特性。所提出的微环谐振器具有大调谐范围和双偏振波长调谐的特点。
