We present an experimental study of thermally induced self-focusing effects and interactions of incoherent light beams in strontium barium niobate waveguides. Depending on the input power, a single parallel beam is strongly focused inside the sample up to diameters of several micrometers. For higher input power we observe the splitting of the beam in a sequence of several spots. We demonstrate that these thermally induced refractive-index patterns can be used to focus and deflect an incoherent guided probe beam in the waveguide with time constants below 1 ms.
© 1998 Optical Society of America
(130.0130) Integrated optics : Integrated optics
(160.6840) Materials : Thermo-optical materials
(190.4870) Nonlinear optics : Photothermal effects
(230.7390) Optical devices : Waveguides, planar
D. Kip, E. Krätzig, V. Shandarov, and P. Moretti, "Thermally induced self-focusing and optical beam interactions in planar strontium barium niobate waveguides," Opt. Lett. 23, 343-345 (1998)