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arXiv · 2412.12943

Confocal polarization tomography of dielectric nanocavities

Frederik Schröder·Martin P. van Exter·Meng Xiong·George Kountouris·Martijn Wubs·Philip T. Kristensen·Nicolas Stenger
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Abstract

We employ polarization tomography to characterize the modal properties of a dielectric nanocavity with sub-wavelength mode confinement. Our analysis of reflection spectra shows that the Fano-lineshape depends strongly on the polarization in a confocal configuration, and that the lineshape can be transformed into a Lorentzian-like peak for a certain polarization. For this polarization setting, the background is almost fully suppressed in a finite range of frequencies. This enables us to identify another resonance that has not yet been experimentally reported for these nanocavities. Lastly, we use symmetry-forbidden polarizations and show that, surprisingly, the modal resonance features of the system remain visible.

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Frederik Schröder, Martin P. van Exter, Meng Xiong, George Kountouris, Martijn Wubs, Philip T. Kristensen, Nicolas Stenger. 2024-12-17. Confocal polarization tomography of dielectric nanocavities. https://arxiv.org/abs/2412.12943

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