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arXiv · 1502.00698

Large-angle quasi-self-collimation effect in a rod-type photonic crystal

Ming Li·Wei Li·Haiyang Huang·Jing Wang·You Li·Aimin Wu·Zhen Sheng·Xi Wang·Shichang Zou·Fuwan Gan
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Abstract

A rod-type photonic crystal (PC) with a rectangular lattice shows a large-angle quasi-self-collimation (quasi-SC) effect by changing the symmetry of its rectangular lattice to straighten one of the isofrequency contours. To investigate the straightness of the isofrequency contour as well as the quasi-SC effect, we propose a straightness factor L based on the method of least squares. With L smaller than L0 (L0 = 0.01 is the critical value), the isofrequency contour is sufficiently straight to induce quasi-SC effect with the beam quasi-collimating in the structure. Furthermore, the efficiency of light coupling to the quasi-SC PC is studied, and can be greatly improved by applying a carefully designed antireflection layer.

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Ming Li, Wei Li, Haiyang Huang, Jing Wang, You Li, Aimin Wu, Zhen Sheng, Xi Wang, Shichang Zou, Fuwan Gan. 2015-02-03. Large-angle quasi-self-collimation effect in a rod-type photonic crystal. https://arxiv.org/abs/1502.00698

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