We present an analytical study of a third-harmonic generation process by surface plasmon polaritons at a Kerr-nonlinear-metal/dielectric interface. Using a planar silver/vacuum interface, we obtain a solution to the frequency-tripling process, showing a semibound third-harmonic surface wave. Unlike the fundamental surface-bound mode, the nonlinear signal radiates into the metal, while remaining bound at the dielectric side of the interface. The propagation of the tripled frequency wave into the metal is generally lossy, except within a narrow range of ultraviolet frequencies, where it is minimally attenuated. The latter is enabled by a transparency window that is unique to the permittivity of silver.
© 2014 Optical Society of America
Original Manuscript: February 28, 2014
Revised Manuscript: May 19, 2014
Manuscript Accepted: May 20, 2014
Published: June 23, 2014
Yan Guo and Miriam Deutsch, "Third-harmonic generation at a silver/vacuum interface using surface plasmon polaritons," Opt. Lett. 39, 3860-3863 (2014)