Wigner spectrograms for femtosecond pulse-shaped heterodyne and autocorrelation measurements

We develop a mixed time-frequency representation for the calculation and interpretation of coherent optical measurements. Heterodyne and autocorrelation signals are expressed in terms of a mixed material response function and a Wigner distribution for the incoming pulses, the detected field, and the gating device. Applications to pump-probe spectroscopy, spontaneous light emission, and impulsive four-wave mixing (three-pulse echoes) are discussed.