We show that useful noninstantaneous, nonlinear phase shifts can be obtained from cascaded quadratic processes in the presence of group-velocity mismatch. The two-field nature of the process permits responses that can be effectively advanced or retarded in time with respect to one of the fields. There is an analogy to a generalized Raman-scattering effect, permitting both red and blueshifts of short pulses. We expect this capability to have many applications in short-pulse generation and propagation, such as the compensation of Raman-induced effects and high-quality pulse compression, which we discuss.
© 2004 Optical Society of America
(190.0190) Nonlinear optics : Nonlinear optics
(190.2640) Nonlinear optics : Stimulated scattering, modulation, etc.
(190.5650) Nonlinear optics : Raman effect
(190.7110) Nonlinear optics : Ultrafast nonlinear optics
(320.5520) Ultrafast optics : Pulse compression
Fatih Ö. Ilday, Kale Beckwitt, Yi-Fan Chen, Hyungsik Lim, and Frank W. Wise, "Controllable Raman-like nonlinearities from nonstationary, cascaded quadratic processes," J. Opt. Soc. Am. B 21, 376-383 (2004)