Slab waveguide with air core layer and anisotropic left-handed material claddings as a sensor

A three-layer slab waveguide with air core layer and anisotropic left-handed material claddings is investigated for sensing applications. Different from the waveguide mode sensors and surface plasmon resonance sensors in which the analyte is placed in the evanescent field region, the proposed sensor contains the sample in the core region that supports the oscillating field. Due to the strong concentration of the electromagnetic field in the analyte medium, the proposed device exhibits unusual sensitivity enhancement. The simulations revealed that the sensitivity improvement of TE₃ mode compared to conventional evanescent wave sensor is approximately a factor of 20.