Experimental determination of a surface wave at the one-dimensional photonic crystal-metal interface

For the first time, to the best of our knowledge, the existence of a surface wave at the one-dimensional photonic crystal (PC)-metal interface is verified experimentally. That surface mode is excited for both transverse electric and transverse magnetic polarizations in the frequency region where one of the bandgaps of the PC overlaps with the region below the plasma frequency of the metal in the frequency wave-vector space and is observed even under normal incidence from vacuum. For a fixed frequency its angular position is very sensitive to the thickness of the one-dimensional photonic-crystal layer adjacent to the metal. (C) 2008 Optical Society of America.