On-chip parallel Fourier transform spectrometer for broadband selective infrared spectral sensing.

Area of Science:

• Optoelectronics
• Spectroscopy
• Materials Science

Background:

• Contactless chemical analysis using optical spectrometers is crucial for various applications.
• Widespread deployment of optical spectrometers is hindered by their size and cost.
• Chip-scale spectrometers face challenges in broad spectral range operation and achieving fine spectral resolution.

Purpose of the Study:

• To develop a compact, cost-effective optical spectrometer for widespread chemical analysis.
• To overcome the limitations of spectral range and resolution in chip-scale spectrometers.
• To introduce and validate a novel parallel Fourier transform infrared (FTIR) spectroscopy concept.

Main Methods:

• Implementation of a Micro-Electro Mechanical Systems (MEMS)-based FTIR spectrometer on a silicon chip.
• Integration of a movable micro-mirror for infrared spectral range operation.
• Development and validation of a parallel (multi-core) FTIR concept using multiple interferometers.

Main Results:

• The MEMS-based FTIR spectrometer successfully operated over a broad spectral range.
• The parallel FTIR concept with 4 interferometers achieved approximately 3 times better spectral resolution.
• The device successfully monitored atmospheric greenhouse gases, measuring and discriminating methane absorption bands.

Conclusions:

• The developed MEMS-based FTIR spectrometer offers a promising solution for compact and cost-effective chemical analysis.
• The parallel FTIR concept effectively overcomes fundamental limits in spectral resolution for chip-scale devices.
• The technology demonstrates potential for environmental monitoring and chemical screening applications.