Autor: |
Lochbaum A; Institute of Electromagnetic Fields (IEF), ETH Zurich, 8092 Zurich, Switzerland., Dorodnyy A; Institute of Electromagnetic Fields (IEF), ETH Zurich, 8092 Zurich, Switzerland., Koch U; Institute of Electromagnetic Fields (IEF), ETH Zurich, 8092 Zurich, Switzerland., Koepfli SM; Institute of Electromagnetic Fields (IEF), ETH Zurich, 8092 Zurich, Switzerland., Volk S; Materials and Device Engineering (MaDE) Group, ETH Zurich, 8092 Zurich, Switzerland., Fedoryshyn Y; Institute of Electromagnetic Fields (IEF), ETH Zurich, 8092 Zurich, Switzerland., Wood V; Materials and Device Engineering (MaDE) Group, ETH Zurich, 8092 Zurich, Switzerland., Leuthold J; Institute of Electromagnetic Fields (IEF), ETH Zurich, 8092 Zurich, Switzerland. |
Abstrakt: |
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 CO 2 . Simultaneously, the metamaterials' angle-independence is maintained, enabling an optically efficient, millimeter-scale cavity. With a CO 2 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. |