Topological optics with 3D-tangle laser solitons

• Published in: Journal of physics. Conference series 2020-03, Vol.1461 (1), p.12143
• Main Authors: Fedorov, S V, Rosanov, N N, Veretenov, N A
• Format: Article
• Language: English
• Subjects: Lasers; Parameters; Perturbation; Physics; Radiation; Solitary waves; Temperature; Topology; Vortices; Wave fronts
• ISSN: 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/1461/1/012143

We analyse, theoretically and numerically, stable localized 3D- structures with radiation wavefront singularities in lasers or laser media with fast saturable absorption; radiation has a fixed polarization state. These laser solitons' internal structure is characterized by their skeletons, which consist of vortex lines where the field vanish and radiation phase changes by 2πm with integer m - topological charge - as a result of a round-trip around the line. The vortex lines are oriented according the direction of radiation phase increase; high-order vortex lines (m>1) are unstable and split into m lines with m=1. Complexes of fundamental (without vortices when isolated) laser solitons have unclosed vortex lines. Presented are topological laser solitons with vortex lines, which are unclosed and closed, unknotted and knotted, unlinked and linked. Various types of the solitons are stable in different, but overlapping domains of the scheme parameters; a slow variation of such parameters leads to hysteretic variations of solitons' characteristics. Such hysteresis is reversible if soliton's topology does not change during the parameters' variation, and irreversible in the opposite case. The increased stability of dissipative solitons and the preservation of the topological characteristics of structures under perturbations make topological laser solitons promising for information applications.