Nonlinearity-mediated soliton ejection from trapping potentials in nonlocal media

We address the properties of optical solitons in thermal nonlinear media with a local refractive index defect that is capable of trapping solitons launched close to the sample boundary despite the boundary-mediated forces that tend to deflect all beams toward the center of the sample. We show that while such forces become more pronounced with an increasing of the input beam power the defect can trap only light below a critical power above which solitons are ejected. The dynamics of soliton ejection and the subsequent propagation may be controlled.

Figure 1

(a) Profiles of solitons with $b=3$ and $b=13$ at $p=1$, $d=10$. Shaded region indicates trapping potential. (b) Integral soliton center versus $b$ at $p=1$. The cutoff value of propagation constant at $d=3$ is given by $b=116.9$. All quantities are plotted in arbitrary dimensionless units.

Figure 2

Propagation constant cutoff versus $d$ at $p=1$ (a) and versus $p$ at $d=10$ (b). Maximal energy flow of trapped soliton versus $d$ at $p=1$ (c) and versus $p$ at $d=10$ (d). All quantities are plotted in arbitrary dimensionless units.

Figure 3

Dynamics of propagation of Gaussian beams with (a) different amplitudes at $\alpha =0$ and (b) with different input tilts at $A=0.93$ for $d=10$, $p=1$. The intensity distributions corresponding to different amplitudes or tilts are superimposed. (c) Critical tilt versus input amplitude at $d=10$, $p=1$. All quantities are plotted in arbitrary dimensionless units.