Spatial dissipative solitons in graphene-based active random metamaterials

Ashis Paul; Andrea Marini; Samudra Roy

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arXiv · 2201.04504

Spatial dissipative solitons in graphene-based active random metamaterials

Ashis Paul·Andrea Marini·Samudra Roy

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Abstract

We investigate dissipative nonlinear dynamics in graphene-based active metamaterials composed of randomly dispersed graphene nano-flakes embedded within an externally pumped gain medium. We observe that graphene saturable nonlinearity produces a sub-critical bifurcation of nonlinear modes, enabling self-organization of the emitted radiation into several dissipative soliton structures with distinct topological charges. We systematically investigate the existence domains of such nonlinear waves and their spatio-temporal dynamics, finding that soliton vortices are unstable, thus enabling self-organization into single dissipative structures with vanishing topological charge, independently of the shape of the graphene nano-flakes. Our results shed light on self-organization of coherent radiation structures in disordered systems and are relevant for future cavity-free lasers and amplifier designs.

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Ashis Paul, Andrea Marini, Samudra Roy. 2022-01-12. Spatial dissipative solitons in graphene-based active random metamaterials. https://arxiv.org/abs/2201.04504

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