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تسجيل مستخدم جديدFlat-band localization and self-collimation of light in photonic crystals
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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 $Gammarightarrow X$ line, but dispersive along the $Gammarightarrow Y$ 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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