title: Cerenkov-type second-harmonic generation with fundamental beams of different polarizations.
abstract: We analyze the conical second-harmonic generation via Cerenkov-type phase matching in two-dimensional decagonal nonlinear photonic quasi-crystals for linear, circular, and elliptical polarized fundamental beams. Depending on the polarization state, we observe either centrosymmetric or noncentrosymmetric intensity modulation of the second-harmonic rings. We explain this effect by employing the concept of effective quadratic nonlinearity combined with the hexagonal symmetry of the individual ferroelectric domains.
authors.affiliation: Max-Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
authors.forename: Yan
authors.initials: Y
authors.lastname: Sheng
authors.forename: Solomon M
authors.initials: SM
authors.lastname: Saltiel
authors.forename: Wieslaw
authors.initials: W
authors.lastname: Krolikowski
authors.forename: Ady
authors.initials: A
authors.lastname: Arie
authors.forename: Kaloian
authors.initials: K
authors.lastname: Koynov
authors.forename: Yuri S
authors.initials: YS
authors.lastname: Kivshar