We address the existence and properties of optical solitons excited in thermal nonlinear media with a transverse refractive index gradient. The interplay between the nonlocality of the thermal nonlinearity and the linear refractive index enables generating controllable switching from surface soliton propagating near the sample edges to bulk solitons. Beam steering associated with the different soliton output locations can be achieved by varying the input light intensity.
Ye, F., Kartashov, Y.V., Hu, B., Torner, L. Power-dependent soliton steering in thermal nonlinear media. "Optics letters", Agost 2009, vol. 34, núm. 17, p. 2658-2660.