Are time- and frequency-domain nonlinear spectroscopies related bya Fourier transform?

摘要

It is commonly believed that nonlinear-spectroscopic techniquesninvolving nearly monochromatic beams, in which one or more beamnfrequencies are varied, are in some sense the "Fourier transforms" ofntechniques involving ultrashort pulses, in which one or more pulsendelays are varied. We find that, while the above Fourier transform doesnhold for classical problems, it fails badly in semi-classical nonlinearnspectroscopy