Midinfrared surface plasmon sensor based on a substrateless metal mesh

A midinfrared mass sensor based on high quality factor surface plasmon modes was designed,fabricated, and tested by infrared spectroscopy for the detection of nanometric layers of dielectric materials. Substrate removal below a metal mesh with period of 2 m results in the coupling between degenerate surface plasmon modes on the two surfaces, resulting in a quality factor up to33 for the antisymmetric mode. The presented substrateless metal mesh integrates mass sensing capability together with midinfrared spectroscopy, and is therefore of potential interest for substance-selective environmental and biomedical sensing applications