Compact Mid-Infrared Gas Sensing Enabled by an All-Metamaterial Design.
Alexander LochbaumAlexander DorodnyyUeli KochStefan M KoepfliSebastian VolkYuriy FedoryshynVanessa WoodJuerg LeutholdPublished in: Nano letters (2020)
The miniaturization of mid-infrared optical gas sensors has great potential to make the "fingerprint region" between 2 and 10 μm accessible to a variety of cost-sensitive applications ranging from medical technology to atmospheric sensing. Here we demonstrate a gas sensor concept that achieves a 30-fold reduction in absorption volume compared to conventional gas sensors by using plasmonic metamaterials as on-chip optical filters. Integrating metamaterials into both the emitter and the detector cascades their individual filter functions, yielding a narrowband spectral response tailored to the absorption band of interest, here CO2. Simultaneously, the metamaterials' angle-independence is maintained, enabling an optically efficient, millimeter-scale cavity. With a CO2 sensitivity of 22.4 ± 0.5 ppm·Hz-0.5, the electrically driven prototype already performs at par with much larger commercial devices while consuming 80% less energy per measurement. The all-metamaterial sensing concept offers a path toward more compact and energy-efficient mid-infrared gas sensors without trade-offs in sensitivity or robustness.
Keyphrases
- room temperature
- low cost
- carbon dioxide
- high resolution
- healthcare
- magnetic resonance imaging
- optical coherence tomography
- computed tomography
- high throughput
- particulate matter
- climate change
- mass spectrometry
- magnetic resonance
- air pollution
- risk assessment
- quantum dots
- image quality
- quality control
- energy transfer