Pulse-to-pulse normalization of time-resolved Fourier transform emission experiments in the near infrared

The signal-to-noise ratio in a time-resolved Fourier transform (FT) infrared emission experiment is improved by pulse-to-pulse normalization. The signal from the FT spectrometer is normalized by the total infrared fluorescence produced on each laser pulse. A factor of 20 enhancement in signal-to-noise ratio is demonstrated with normalization when the fluctuation of the laser pulse energy is the dominant noise source. Applications are discussed pertaining to cases where other noise sources such as detector and amplifier noise cannot be neglected and when information from the time evolution of the spectrum is required.