Nonlinear rotation of 3D dark spatial solitons in a Gaussian laser beam

Dark spatial solitons have recently been the subject of intense theoretical and experimental study because of their potential in all-optical switching. The possibility of creating stable light-controllable waveguides which can be used to propagate signal carrying beams has been explored in the case of 2D dark solitons. An extension of this concept of guiding light by light to 3D could allow reconfigurable “optical fibres” to be written in bulk media. However, in the 3D geometry only “black” solitons exist, preventing the use of the soliton phase, as in the 2D case, to control the soliton direction and hence that of the induced waveguides. Thus, in the 3D geometry a different means of reconfiguring the soliton induced waveguides is required. Here we demonstrate nonlinearity induced rotation of 3D dark solitons at the output of a nonlinear medium. By changing the beam intensity (or the material nonlinearity) a 3D soliton embedded off-axis in a Gaussian beam can be made to rotate around that axis by up to 90°. The induced waveguide therefore links a single input port to an array of output ports in a geometry akin to a rotary switch