Simple experimental technique for analytically characterizing ultrashort laser pulses

In this paper we will describe general methodology that allows the phase of an unknown pulse to be analytically obtained. This technique brings together time-frequency and interferometric techniques while at the same time it maintains robust error checking capabilities. Besides, it does not rely on the use of iterative retrieval algorithms and does rely on Fourier analysis. Our methodology only requires a simple collinear autocorrelator whose output is spectrally resolved as a function of delay. We call this technique Measurement of Electric Field by Interferometric Spectral Trace Observation (MEFISTO).