A four-layer slab waveguide structure with a lossy left-handed material (LHM) core layer is investigated
as a surface sensor for detection any change in an adlayer thickness and refractive index. The sensitivities
of the effective refractive index to any change in the refractive index/thickness of the adlayer are derived
and studied with the parameters of the LHM. It is found that a slight change in the real parts of the
permittivity and permeability of the LHM can significantly improve the sensitivity of the proposed sensor