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arXiv · 2209.10772

Compact spectrometer based on disordered multi-mode interferometer

Ankit Poudel·Pravin Bhattarai·Rijan Maharjan·Richard J Curry·Iain F Crowe·Ashim Dhakal
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Abstract

We demonstrate a compact (40 ${\mu}$m $\times$ 260 ${\mu}$m) spectrometer based on multimode interference aided by scattering of light from random SiO$_2$-filled hole arrays on a silicon-on-insulator platform. We characterize the performance of the spectrometer for wavelengths around 1310 nm, and report that the spectrometer can reconstruct a broadband $\sim$ 67 nm source, as well as Lorentzian probes of $\sim$ 1 nm bandwidth. This compact nanometer level resolution spectrometer can be fabricated at a low cost for lab-on-a-chip sensing and imaging applications.

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Ankit Poudel, Pravin Bhattarai, Rijan Maharjan, Richard J Curry, Iain F Crowe, Ashim Dhakal. 2022-09-22. Compact spectrometer based on disordered multi-mode interferometer. https://doi.org/10.1364/oe.484199

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