Elliptical optical solitary waves in a finite nematic liquid crystal cell

PHYSICA D-NONLINEAR PHENOMENA

卷:301

Article

Minzoni, Antonmaria A.¹  Sciberras, Luke W.^1,2  Smyth, Noel F.^3,4  Worthy, Annette L.² 

[1] Univ Nacl Autonoma Mexico, Fenomenos Nonlineales & Mecan FENOMEC, Dept Math & Mech, Inst Invest Matemat Aplicadas & Sistemas, Mexico City 01000, DF, Mexico

[2] Univ Wollongong, Sch Math & Appl Stat, Wollongong, NSW 2522, Australia

[3] Univ Edinburgh, Sch Math, Edinburgh EH9 3FD, Midlothian, Scotland

[4] Univ Edinburgh, Maxwell Inst Math Sci, Edinburgh EH9 3FD, Midlothian, Scotland

关键词: Liquid crystal;    Soliton;    Elliptic solitary wave;    Nematicon;    Modulation theory;   

DOI  :  10.1016/j.physd.2015.03.005

来源: Elsevier

【 摘 要 】

The addition of orbital angular momentum has been previously shown to stabilise beams of elliptic cross-section. In this article the evolution of such elliptical beams is explored through the use of an approximate methodology based on modulation theory. An approximate method is used as the equations that govern the optical system have no known exact solitary wave solution. This study brings to light two distinct phases in the evolution of a beam carrying orbital angular momentum. The two phases are determined by the shedding of radiation in the form of mass loss and angular momentum loss. The first phase is dominated by the shedding of angular momentum loss through spiral waves. The second phase is dominated by diffractive radiation loss which drives the elliptical solitary wave to a steady state. In addition to modulation theory, the chirp variational method is also used to study this evolution. Due to the significant role radiation loss plays in the evolution of an elliptical solitary wave, an attempt is made to couple radiation loss to the chirp variational method. This attempt furthers understanding as to why radiation loss cannot be coupled to the chirp method. The basic reason for this is that there is no consistent manner to match the chirp trial function to the generated radiating waves which is uniformly valid in time. Finally, full numerical solutions of the governing equations are compared with solutions obtained using the various variational approximations, with the best agreement achieved with modulation theory due to its ability to include both mass and angular momentum losses to shed diffractive radiation. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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