Spatial-temporal waveform synthesis and detection by wave-mixing with second-order nonlinearities

Summary form only given. Space-time conversions have been proposed for ultrafast optical communications as a possible technique for bridging the gap between slow electronic modulation and detection and the large capacity of an optical fiber. We present for the first time, to the best of our knowledge, optical waveform synthesis at femtosecond rates. Such rates can only be accomplished by wave mixing the spatial and temporal fields in a material exhibiting bound electron nonlinearities. However, the /spl chi//sup 3/ nonlinearity required for spatial-temporal four-wave mixing is inherently small. We employ an alternative arrangement based on cascaded second-order nonlinearities (CSN) configured for an equivalent of a four-wave interaction in /spl chi//sup 2/ medium. The CSN arrangement consists of a frequency-sum process followed by a frequency-difference process satisfying the type-II non-collinear phase matching condition.