Lasers capable of generating picosecond and femtosecond pulses of light are now firmly established and are widely deployed for applications ranging from basic science to fiber communications to biomedical imaging. Enhanced functionalities are possible when ultrashort pulses can be programmably reshaped into user specified waveforms. This talk will begin with a brief general introduction into ultrafast optics and then specifically address the topic of shaping ultrafast laser fields. Because the time scales involved are much too fast for direct application of (opto)electronic modulator technologies, all-optical approaches are employed. In particular, a Fourier synthesis waveform generation method, in which different optical frequency components contained in an ultrashort pulse are spatially separated, manipulated in parallel using a spatial light modulator, and then recombined, has enjoyed considerable success. After discussing the basics of pulse shaping, I will survey some of the applications areas, with an emphasis on broadband photonic signal processing relevant to lightwave communications and ultrabroadband radio-frequency electromagnetics.
Stewart Center, Purdue University, West Lafayette, IN