Long-range surface modes of metal-clad four-layer waveguides.

The surface modes of metal-clad four-layer waveguides were theoretically analyzed. We showed that the long-range surface modes can be excited in such waveguides. The long-range surface modes were experimentally studied with the angle scanning attenuated-total-reflection method; the dependence of wave vector and loss of these modes on the waveguide parameters were measured. Experimental results were in good agreement with theoretical calculations.