Abstract

A long-standing problem in ultrafast optics is that of measuring the electrical field of a light pulse whose duration is shorter than the response time of a photodetector. We analyze a general scheme that uses an arbitrary combination of linear filters, interferometers and nonlinear detectors, and elucidate the properties that allow determination of the temporal or spectral phase of the pulse. In particular we discuss the possibility of phase determination via a linear interferometer and a square-law detector, and derive general conditions on the speed of the detector that allow us to identify the limitations of certain measurement schemes.

© 1993 Optical Society of America