IEEE Journal of Selected Topics in Quantum Electronics

Simultaneous Enhancement of Bandwidth and Group Index of Slow Light via Metamaterial Induced Transparency With Double Bright Resonators

Jiawei Cong, Gaige Zheng, Binfeng Yun, Zhiqiang Zhou

Published Sep 15, 2014• 7 citations

Abstract

We propose a design strategy to alleviate the tradeoff between the wide frequency band and large group index of metamaterial induced slow light. It is realized with a structure consisting of double bright resonators and a single dark resonator in each unit cell. Such a structure enables the slow light with enhanced bandwidth and increased group index simultaneously than the conventional scheme with only one bright resonator. The origin is attributed to the stronger bright-dark coupling and steeper dispersion in the double bright structure. The slow light characteristics are analytically demonstrated with the coupled oscillator model and verified by the full-wave simulations. The presented design rule may offer an avenue to realize broadband slow light devices.

DOI: 10.1109/jstqe.2014.2354639

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