Confocal polarization tomography of dielectric nanocavities

2024/12/17 by Schröder, Frederik, van Exter, Martin P., Xiong, Meng +4
#FOS: Physical sciences #Optics (physics.optics)

paper · doi:10.48550/arxiv.2412.12943

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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