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arXiv · 2503.03289

Group Delay Dispersion Measurements of Novel Multilayer Interference Coatings in the Mid-Infrared Spectral Regime

Ulrich Galander·Maximilian Prinz·Lukas W. Perner·Oliver H. Heckl
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Abstract

We present the methods and results for broadband group delay dispersion measurements for all-monocrystalline and amorphous-crystalline hybrid supermirrors, as well as an all-amorphous mirror in the wavelength range from \SIrange{2.5}{4.8}{\micro \metre}. Measurements are performed using a custom-built white light interferometer that allows for balanced and unbalanced measurement configurations. We compare the results to theoretical transfer-matrix method simulations and an alternative measurement using a commercial Fourier-transform infrared spectrometer. Additionally, we investigate group delay dispersion by direct differentiation using a local polynomial smoothing approach (Savitzky-Golay filter) and find strong consistency between our results, the theoretical prediction and the estimation using this method.

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Ulrich Galander, Maximilian Prinz, Lukas W. Perner, Oliver H. Heckl. 2025-03-05. Group Delay Dispersion Measurements of Novel Multilayer Interference Coatings in the Mid-Infrared Spectral Regime. https://arxiv.org/abs/2503.03289

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