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arXiv · 1801.08671

Flat-band localization and self-collimation of light in photonic crystals

Nojoon Myoung·Hee Chul Park·Ajith Ramachandran·Elefterios Lidorikis·Jung-Wan Ryu
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Abstract

We investigate the optical properties of a photonic crystal composed of a quasi-one-dimensional flat-band lattice array through finite-difference time-domain simulations. The photonic bands contain flat bands (FBs) at specific frequencies, which correspond to compact localized states as a consequence of destructive interference. The FBs are shown to be nondispersive along the $\Gamma\rightarrow X$ line, but dispersive along the $\Gamma\rightarrow Y$ line. The FB localization of light in a single direction only results in a self-collimation of light propagation throughout the photonic crystal at the FB frequency.

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Nojoon Myoung, Hee Chul Park, Ajith Ramachandran, Elefterios Lidorikis, Jung-Wan Ryu. 2018-01-26. Flat-band localization and self-collimation of light in photonic crystals. https://doi.org/10.1038/s41598-019-39471-0

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