Edge and bulk dissipative solitons in modulated PT-symmetric waveguide arrays

Abstract

We address dissipative soliton formation in modulated PT-symmetric continuous waveguide arrays composed from waveguides with amplifying and absorbing sections, whose density gradually increases (due to decreasing waveguide separation) either towards the center of the array or towards its edges. In such a structure the level of gain/loss at which PT-symmetry gets broken depends on the direction of increase of the waveguide density. Breakup of the PT-symmetry occurs when eigenvalues of modes localized in the region, where waveguide density is largest, collide and move into complex plane. In this regime of broken symmetry the inclusion of focusing Kerr-type nonlinearity of the material and weak two-photon absorption allows to arrest the growth of amplitude of amplified modes and may lead to the appearance of stable attractors either in the center or at the edge of the waveguide array, depending on the type of array modulation. Such solitons can be stable, they acquire specific triangular shapes and notably broaden with increase of gain-loss level. Our results illustrate how spatial array modulation that breaks PT-symmetry locally can be used to control specific location of dissipative solitons forming in the array.

4 pages, 5 figures, to appear in Optics Letters

References in corpus (13)

• Making Sense of Non-Hermitian Hamiltonians
• Unidirectional Nonlinear PT-symmetric Optical Structures
• Solitons in PT-symmetric nonlinear lattices
• Light stops at exceptional points
• Stable localized modes in asymmetric waveguides with gain and loss
• Families of stationary modes in complex potentials
• Unbreakable PT-symmetry of solitons supported by inhomogeneous defocusing nonlinearity
• Dynamics of surface solitons at the edge of chirped optical lattices
• Observation of surface solitons in chirped waveguide arrays
• Soliton dynamics in symmetric and non-symmetric complex potentials
• Mode pairs in $\mathcal{P}\mathcal{T}$-symmetric multimode waveguides
• Staggered $\mathcal{P}\mathcal{T}$-symmetric ladders with cubic nonlinearity
• Asymmetric soliton mobility in competing linear-nonlinear PT-symmetric lattices

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• Existence and Stability of Dissipative Solitons in a Dual-Waveguide Lattice with Linear Gain and Nonlinear Losses