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Tight-binding photonic bands in metallophotonic waveguide networks and flat bands in kagome lattices

Shimpei Endo·Takashi Oka·Hideo Aoki
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Abstract

We propose that we can realize "tight-binding photonic bands" in metallophotonic waveguide networks, where the photonic bound states localized around the crossings of a network form a tight-binding band. The formation of bound states at the crossings is distinct from the conventional bound states at defects or virtual bound states in photonic crystals, but comes from a photonic counterpart of the zero-point states in wave mechanics. Model calculations show that the low-lying photon dispersions are indeed described accurately by the tight-binding model. To exemplify how we can exploit the tight-binding analogy for a {\it designing} of photonic bands, we propose a "flat photonic band" in the kagome network, in which the photonic flat band is shown to arise with group velocities that can be as small as 1/1000 times the velocity of light in vacuum.

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Shimpei Endo, Takashi Oka, Hideo Aoki. 2010-03-12. Tight-binding photonic bands in metallophotonic waveguide networks and flat bands in kagome lattices. https://doi.org/10.1103/physrevb.81.113104

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