Breakdown of Dirac dynamics in honeycomb lattices due to nonlinear interactions

Scientific paper - Original scientific paper

• Author: Omri Bahat-Treidel
• Author: Or Peleg
• Author: Mordechai Segev
• Author: Hrvoje Buljan
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

We study the dynamics of coherent waves in nonlinear honeycomb lattices and show that nonlinearity breaks down the Dirac dynamics. As an example, we demonstrate that even a weak nonlinearity has major qualitative effects on one of the hallmarks of honeycomb lattices: conical diffraction. Under linear conditions, a circular input wave packet associated with the Dirac point evolves into a ring, but even a weak nonlinearity alters the evolution such that the emerging beam possesses triangular symmetry, and populates Bloch modes outside of the Dirac cone. Our results are presented in the context of optics, but we propose a scheme to observe equivalent phenomena in Bose-Einstein condensates.

• Keywords (english): Dirac equation; honeycomb lattice; nonlinear interactions
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review A
• Numbering: vol. 82, no. 1, 013830
• p-ISSN: 1050-2947
• DOI: https://doi.org/10.1103/PhysRevA.82.013830
• URN:NBN: urn:nbn:hr:217:292326
• Publication: 2010
• Project: Number: 119-0000000-1015; Title (croatian): Nelinearne pojave i valna dinamika u fotoničkim sustavima; Leader: Hrvoje Buljan; Jurisdiction: Croatia; Funding stream: ZP
• Document URL: http://link.aps.org/doi/10.1103/PhysRevA.82.013830
• Type of resource: Text
• Access conditions: Open access
• Public note: Copyright (2010) by the American Physical Society. Received 26 April 2010; published 26 July 2010.
• Created on: 2019-11-02 18:55:05