Soliton Aided Propagation and Routing of Vortex Beams in Nonlocal Media

Self-confined light waves in nematic liquid crystals

“…In a similar manner, the medium nonlocality can also stabilise the interaction of optical vortices [210]. Finally, the stabilising influence of co-propagating coaxial nematicons caused by raising the director profile under the singularity (vortex core) can also stabilise optical vortices undergoing refraction through dielectric interfaces or in non-uniform environments [211,212,213].…”

Interactions of Self-Localised Optical Wavepackets in Reorientational Soft Matter

“…This ultimately results in the destruction of the vortex, Figure 5d-f, and its break up into solitary waves. In later work, it was found that the stability of an optical vortex propagating through a dielectric interface can be enhanced by a co-propagating coaxial nematicon as the latter acts as a waveguide and helps to keep the vortex together by confining a large amount of its high amplitude field distribution [85].…”

Light-Induced Waveguides in Nematic Liquid Crystals

“…Let us now consider the guidance of an optical vortex by a co-propagating nematicon, as studied in [19], [20], [21]. As expected on the basis of the highly nonlocal medium response, the nematicon acts as a waveguide even for a vortex: while an isolated vortex could not survive interaction with an index perturbation or interface and undergo stable refraction, in the presence of a coaxial nematicon it gets stabilized by the nonlinear index potential and can be deviated/refracted [19], [20], [21]. We consider a nematicon and a vortex to be generated from polarized beams of the same wavelength, so that we can take D u = D v = 1 and A u = A v = 1 in terms of the two color nematic equations (5)- (7).…”

“…5(c) and (d). The stable routing of an optical vortex by a nematicon around a localized index change can be extended to the classical optics problem of a beam refracted at a linear interface between two regions of different refractive indices [21]. To eliminate numerical instabilities, the linear interface between the regions of different refractive indices in the (x, z) plane was smoothed as Figure 6 illustrates the refraction of a guided vortex, as governed by the nematic equations (12)- (14).…”

“…Furthermore, since NLC are nonlocal in that the response to an optical beam extends far beyond its waist [1], [2], [15], nematicons can act on each other at a distance through the medium [16], [17], [18]. Finally, a nematicon waveguide can stabilize beams which tend to become unstable upon interacting with, for example, refractive index perturbations [19], [20], [21]. In the following we shall address these features and properties of nematicon waveguides.…”