Nondestructive mixing characteristics of optical resonance modes investigated using artificial dielectric systems

The nondestructive mixing properties of optical resonance modes were investigated using a structure with a dielectric sandwiched between metallic sub-wavelength cut-through slit-array slabs. For the un-shifted slit-array configuration, the resonance mode repulsion around the intersection was more enhanced for an intermediate dielectric with a greater refractive index, though no anticrossing characteristic was seen for an air-gap structure. On the other hand, a lateral shift of the slit arrays enhanced the mode mixing effects even for an air-gap structure. The geometrically dependent characteristics are interpreted in terms of the difference between the (effective) refractive indices of both sides of the slits.