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arXiv · 2005.05374

Approaching the upper limits of the local density of states via optimized metallic cavities

Wenjie Yao·Mohammed Benzaouia·Owen D. Miller·Steven G. Johnson
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Abstract

By computational optimization of air-void cavities in metallic substrates, we show that the local density of states (LDOS) can reach within a factor of $\approx 10$ of recent theoretical upper limits, and within a factor $\approx 4$ for the single-polarization LDOS, demonstrating that the theoretical limits are nearly attainable. Optimizing the total LDOS results in a spontaneous symmetry breaking where it is preferable to couple to a specific polarization. Moreover, simple shapes such as optimized cylinders attain nearly the performance of complicated many-parameter optima, suggesting that only one or two key parameters matter in order to approach the theoretical LDOS bounds for metallic resonators.

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Wenjie Yao, Mohammed Benzaouia, Owen D. Miller, Steven G. Johnson. 2020-05-11. Approaching the upper limits of the local density of states via optimized metallic cavities. https://doi.org/10.1364/oe.397502

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