title: Nonadiabatic Landau-Zener tunneling in waveguide arrays with a step in the refractive index.
abstract: Landau-Zener tunneling is discussed in connection with optical waveguide arrays. Light injected in a specific band of the Bloch spectrum in the propagation constant can be transmitted to another band, changing its physical properties. This can be achieved using two coupled waveguide arrays with different refractive indices. The step in the refractive index causes wave "acceleration" and thus induces strongly nonadiabatic Landau-Zener tunneling. Theoretically, the analysis is performed by considering a Schrödinger equation in a periodic potential with a step. The region of physical parameters where this phenomenon can occur is analytically determined and a realistic experimental setup is suggested. Its application could allow the realization of light filters.
authors.affiliation: Department of Physics, Tbilisi State University, 3 Chavchavadze Avenue, Tbilisi 0128, Republic of Georgia. khomeriki@hotmail.com
authors.forename: Ramaz
authors.initials: R
authors.lastname: Khomeriki
authors.forename: Stefano
authors.initials: S
authors.lastname: Ruffo