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Fourier transform spectrometer on silicon with thermo-optic non-linearity and dispersion correction.

ABSTRACT: Miniaturized integrated spectrometers will have unprecedented impact on applications ranging from unmanned aerial vehicles to mobile phones, and silicon photonics promises to deliver compact, cost-effective devices. Mirroring its ubiquitous free-space counterpart, a silicon photonics-based Fourier transform spectrometer (Si-FTS) can bring broadband operation and fine resolution to the chip scale. Here we present the modeling and experimental demonstration of a thermally tuned Si-FTS accounting for dispersion, thermo-optic non-linearity, and thermal expansion. We show how these effects modify the relation between the spectrum and interferogram of a light source and we develop a quantitative correction procedure through calibration with a tunable laser. We retrieve a broadband spectrum (7?THz around 193.4?THz with 0.38-THz resolution consuming 2.5?W per heater) and demonstrate the Si-FTS resilience to fabrication variations-a major advantage for large-scale manufacturing. Providing design flexibility and robustness, the Si-FTS is poised to become a fundamental building block for on-chip spectroscopy.

SUBMITTER: Souza MCMM

PROVIDER: S-EPMC5813211 | biostudies-other | 2018 Feb

REPOSITORIES: biostudies-other

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Fourier transform spectrometer on silicon with thermo-optic non-linearity and dispersion correction.

Souza Mario C M M MCMM Grieco Andrew A Frateschi Newton C NC Fainman Yeshaiahu Y

Nature communications 20180214 1

Miniaturized integrated spectrometers will have unprecedented impact on applications ranging from unmanned aerial vehicles to mobile phones, and silicon photonics promises to deliver compact, cost-effective devices. Mirroring its ubiquitous free-space counterpart, a silicon photonics-based Fourier transform spectrometer (Si-FTS) can bring broadband operation and fine resolution to the chip scale. Here we present the modeling and experimental demonstration of a thermally tuned Si-FTS accounting f ...[more]

PMID: 29445152

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Dataset Information

Fourier transform spectrometer on silicon with thermo-optic non-linearity and dispersion correction.

Publications

Fourier transform spectrometer on silicon with thermo-optic non-linearity and dispersion correction.

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