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arXiv · 1902.09415

On the Calculation of the Quality Factor in Contemporary Photonic Resonant Structures

Thomas Christopoulos·Odysseas Tsilipakos·Georgios Sinatkas·Emmanouil E. Kriezis
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Abstract

The correct numerical calculation of the resonance characteristics and, principally, the quality factor $Q$ of contemporary photonic and plasmonic resonant systems is of utmost importance, since $Q$ defines the bandwidth and affects nonlinear and spontaneous emission processes. Here, we comparatively assess the commonly used methods for calculating $Q$ using spectral simulations with commercially available, general-purpose software. We study the applicability range of these methods through judiciously selected examples covering different material systems and frequency regimes from the far-infrared to the visible. We care in highlighting the underlying physical and numerical reasons limiting the applicability of each one. Our findings demonstrate that in contemporary systems (plasmonics, 2D materials) $Q$ calculation is not trivial, mainly due to the physical complication of strong material dispersion and light leakage. Our work can act as a reference for the mindful and accurate calculation of the quality factor and can serve as a handbook for its evaluation in guided-wave and free-space photonic and plasmonic resonant systems.

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Thomas Christopoulos, Odysseas Tsilipakos, Georgios Sinatkas, Emmanouil E. Kriezis. 2019-05-07. On the Calculation of the Quality Factor in Contemporary Photonic Resonant Structures. https://doi.org/10.1364/oe.27.014505

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