Enhanced nonlinearity of the propagation constant of a long-range surface-plasma wave

Abstract

We calculate the power-dependent propagation constant of a surface-plasma wave as a function of the thickness of the metal film on which it propagates when the metal film is bounded by a nonlinear semiconductor. In the case of a Cu film bounded by InSb at a wavelength of ∼5 μm and a temperature of 5 K, we find that the effect of the nonlinearity on the propagation constant is enhanced by a factor of 10 as the metal thickness decreases from 120 to 15 nm.