Abstract
While curved waveguides are fundamental elements in photonics, those induced all optically in nonlinear uniform dielectrics tend to be straight. In uniaxial soft matter with a reorientational response, such as nematic liquid crystals (NLCs), light beams in the extraordinary polarization undergo self-focusing via an increase in refractive index and eventually form spatial solitons, i.e., self-induced waveguides. Hereby we investigate the bending of such waveguides by analyzing the trajectory of solitons in NLCs—nematicons—in the presence of a linearly varying transverse orientation of the optic axis. To this extent, we use and compare two approaches: i) a slowly varying (adiabatic) approximation based on momentum conservation of the nematicon in a Hamiltonian sense; and ii) the Frank–Oseen elastic theory coupled with a fully vectorial and nonlinear beam propagation method. The models provide comparable results in such a non-homogeneously oriented uniaxial medium and predict bent soliton paths with either monotonic or non-monotonic curvatures, enabling the design of curved channel waveguides induced by light beams.
© 2017 Optical Society of America
Full Article | PDF ArticleMore Like This
Michał Kwaśny, Iga Ostromęcka, Bartłomiej W. Klus, and Urszula A. Laudyn
Opt. Mater. Express 13(7) 2071-2082 (2023)
A. Alberucci, M. Peccianti, G. Assanto, G. Coschignano, A. De Luca, and C. Umeton
Opt. Lett. 30(11) 1381-1383 (2005)
Marco Peccianti, Andrea Fratalocchi, and Gaetano Assanto
Opt. Express 12(26) 6524-6529 (2004)