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Stable nonlinear modes sustained by gauge fields

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 نشر من قبل Vladimir Konotop
 تاريخ النشر 2020
  مجال البحث فيزياء
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We reveal the universal effect of gauge fields on the existence, evolution, and stability of solitons in the spinor multidimensional nonlinear Schr{o}dinger equation. Focusing on the two-dimensional case, we show that when gauge field can be split in a pure gauge and a rtext{non-pure gauge} generating rtext{effective potential}, the roles of these components in soliton dynamics are different: the btext{localization characteristics} of emerging states are determined by the curvature, while pure gauge affects the stability of the modes. Respectively the solutions can be exactly represented as the envelopes independent of the pure gauge, modulating stationary carrier-mode states, which are independent of the curvature. Our central finding is that nonzero curvature can lead to the existence of unusual modes, in particular, enabling stable localized self-trapped fundamental and vortex-carrying states in media with constant repulsive interactions without additional external confining potentials and even in the expulsive external traps.

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