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arXiv · 2104.09818

Controllable finite ultra-narrow quality-factor peak in a perturbed Dirac-cone band structure of a photonic crystal slab

Alex Y. Song·Akhil Raj Kumar Kalapala·Ricky Gibson·Kevin James Reilly·Thomas Rotter·Sadhvikas Addamane·Haiwen Wang·Cheng Guo·Ganesh Balakrishnan·Robert Bedford·Weidong Zhou·Shanhui Fan
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Abstract

We show that by using a perturbed photonic Dirac-cone, one can realize ultra-narrow and finite Q-factor peak in the wavevector space, with both the peak value and the width separately tunable. We also discuss a lower bound in the minimal viable width given a peak Q-value while maintaining sufficient Q differentiation among modes. The strong angular and frequency Q-selection finds applications in optical devices where strong angle- and frequency-selection is needed.

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Alex Y. Song, Akhil Raj Kumar Kalapala, Ricky Gibson, Kevin James Reilly, Thomas Rotter, Sadhvikas Addamane, Haiwen Wang, Cheng Guo, Ganesh Balakrishnan, Robert Bedford, Weidong Zhou, Shanhui Fan. 2021-04-20. Controllable finite ultra-narrow quality-factor peak in a perturbed Dirac-cone band structure of a photonic crystal slab. https://doi.org/10.1063/5.0056243

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