The theory of guided waves in metal-dielectric planar multilayer structures is applied to reduce the loss and maximize optical nonlinearity for efficient terahertz-field generation in a surface electromagnetic wave by femtosecond laser pulses confined in a χ(2) nonlinear planar waveguide. For typical parameters of thin-film polymer waveguides and metal-dielectric interfaces, the optimal size of the χ(2) waveguide core providing the maximum efficiency of terahertz plasmon-field generation is shown to be less than the wavelength of the optical pump field.
© 2008 Optical Society of America
Original Manuscript: July 27, 2007
Revised Manuscript: October 12, 2007
Manuscript Accepted: November 9, 2007
Published: January 22, 2008
Roman R. Musin, Qirong Xing, Yanfeng Li, Minglie Hu, Lu Chai, Qingyue Wang, Yuliya M. Mikhailova, Maksim M. Nazarov, Alexander P. Shkurinov, and Aleksei M. Zheltikov, "Design rules for phase-matched terahertz surface electromagnetic wave generation by optical rectification in a nonlinear planar waveguide," Appl. Opt. 47, 489-494 (2008)