Slow light from sharp dispersion by exciting dark photonic angular momentum states

Optics Letters (Impact Factor: 3.29). 02/2013; 38(3):250-2. DOI: 10.1364/OL.38.000250
Source: PubMed


A photonic angular momentum state (PAMS) with a topological charge of m≠±1 is dipole forbidden at all polarizations of free-space incidence due to the existence of a unique helical phase. We show that by indirectly exciting dark PAMSs through coupling with a bright resonant element, a sharply variant transmission behavior and strong dispersion can be achieved. This behavior can subsequently be utilized in slow light. A metamaterial design, in which a group index ng greater than 500 can be achieved, is present.

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