Non-linear control of soliton spiraling in nematic liquid crystals

Spatial soliton interactions, such as crossing, merging and spiraling, have been widely studied in the past years as means to exploit non-locality and ways to implement all-optical signal addressing or processing. With reference to spiraling, if attraction provided by the non-linear potential is exactly balanced by the system momentum, the initial soliton distance remains unchanged over the propagation. This phenomenon has been studied in different materials with Kerr, photorefractive or thermal non-linearities, both theoretically and experimentally. However, all such studies have been conducted acting on the initial conditions or comparing distinct longitudinal sections. Here we present an experimental study on soliton spiraling in nematic liquid crystal with another approach: we gain non-linear control over the two-soliton cluster by simply varying the total power excitation of the system.