Abstract

Numerous ultrashort pulse applications have employed the cascaded-quadratic (χ⁽²⁾: χ⁽²⁾) nonlinearity to produce Kerr-like nonlinear phase shifts [1]. In each of these applications propagation in cubic media is mimicked: an effective nonlinear Schrodinger equation governs propagation, but with features inaccessible from χ⁽³⁾, such as a negative (self-defocusing) Kerr term and Raman- or self-steepening-like terms of controllable sign and magnitude.

© 2007 IEEE