Pyramid diffraction in parity-time-symmetric optical lattices

TL;DR

This paper analytically studies wave packet dynamics in 2D parity-time-symmetric optical lattices, revealing a pyramid diffraction pattern and potential blow-up phenomena in both linear and nonlinear regimes.

Contribution

It introduces a novel fourth-order envelope equation and demonstrates pyramid diffraction patterns in these complex optical systems.

Findings

Pyramid diffraction pattern observed in linear and nonlinear regimes

Derivation of a new fourth-order envelope equation

Blow-up phenomena possible in nonlinear regimes for focusing and defocusing nonlinearities

Abstract

Nonlinear dynamics of wave packets in two-dimensional parity-time-symmetric optical lattices near the phase-transition point are analytically studied. A novel 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.