title: Pyramid diffraction in parity-time-symmetric optical lattices.
abstract: Nonlinear dynamics of wave packets in two-dimensional parity-time-symmetric optical lattices near the phase transition point are analytically studied. A fourth-order equation is derived for the envelope of these wave packets. A pyramid diffraction pattern is demonstrated in both the linear and nonlinear regimes. Blow-up is also possible in the nonlinear regime for both focusing and defocusing nonlinearities.
authors.affiliation: Department of Mathematics and Statistics, University of Vermont, Burlington, Vermont 05401, USA.
authors.forename: Sean
authors.initials: S
authors.lastname: Nixon
authors.forename: Jianke
authors.initials: J
authors.lastname: Yang