title: Large enhancement of third-harmonic generation induced by coupled gap solitons in chi(3) nonlinear photonic crystals.
abstract: It is shown that, in a chi((3)) nonlinear photonic crystal, the third-harmonic conversion efficiency can be enhanced by about three orders of magnitude via the formation of self-organized localized states inside the gaps as compared with that in a bulk medium of the same length with a perfect phase-matching condition. These localized states contain both the fundamental and third-harmonic frequencies located in different gaps. Their existence is a result of both the Kerr effect and the large energy transfer between fundamental and third-harmonic waves.
authors.affiliation: Department of Physics and Institute of Nano Science and Technology (INST), The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Xie
authors.forename: Zhao-Qing
authors.initials: ZQ
authors.lastname: Zhang