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

ABSTRACT: We investigate the optical properties of a photonic crystal (PC) 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 ????X line, prohibiting optical transmission with incident light in x direction. On the other hand, the photonic band for the FB frequency is found to be dispersive along the ????Y line, resulting in nonzero optical transmission. Such anisotropic optical response of the PC due to the FB localization of light in a single direction only results in a self-collimation of light propagation throughout the PC at the FB frequency.

SUBMITTER: Myoung N

PROVIDER: S-EPMC6393537 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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

Myoung Nojoon N Park Hee Chul HC Ramachandran Ajith A Lidorikis Elefterios E Ryu Jung-Wan JW

Scientific reports 20190227 1

We investigate the optical properties of a photonic crystal (PC) 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 Г → X line, prohibiting optical transmission with incident light in x direction. On the other hand, the photonic ban ...[more]

PMID: 30814629

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