Multidimensional metamaterial fluid sensor

We report for the first time on a fluid sensor platform applying simultaneously confined electromagnetic and acoustic waves. Confinement is realized in a so-called phoxonic crystal, a specific version of a metamaterial. Metamaterials are engineered to achieve desired effects by incorporating structural elements of (sub-)wavelength sizes. The sensor platform is a solid plate featuring an array of holes arranged in a square lattice. A defect introduces local resonances and the resonance frequency has been found to depend on refractive index or permittivity and mass attached to the defect.