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arXiv · 1206.0502

A 1.16-μm-radius disk cavity in a sunflower-type circular photonic crystal with ultrahigh quality factor

Xufeng Zhang·Xiankai Sun·Hong X. Tang
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Abstract

We present a 1.16-\mum-radius disk cavity with ultrahigh quality (Q) factor by embedding the disk into a sunflower-type circular photonic crystal (CPC). The band gap of the CPC reduces the bending loss of the whispering-gallery mode of the disk, leading to a simulated Q of 10^7, at least one order of magnitude higher than a bare disk of the same size. The design is experimentally verified with a record high loaded Q of 7.4 \times 10^5 measured from an optimized device fabricated on a silicon-on-insulator substrate.

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Xufeng Zhang, Xiankai Sun, Hong X. Tang. 2012-06-04. A 1.16-μm-radius disk cavity in a sunflower-type circular photonic crystal with ultrahigh quality factor. https://doi.org/10.1364/ol.37.003195

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