A new femtosecond time-resolved interferometer was developed that utilizes interference fringes in the frequency domain to obtain simultaneously difference phase spectra (DPS) and difference transmission spectra with a multichannel spectrometer. For the first time to our knowledge, transient oscillations were observed in DPS and the spectral shift of a probe pulse was time resolved together with the rise in DPS, which is clear evidence for induced phase modulation in absorptive materials.
© 1992 Optical Society of America
E. Tokunaga, A. Terasaki, and T. Kobayashi, "Frequency-domain interferometer for femtosecond time-resolved phase spectroscopy," Opt. Lett. 17, 1131-1133 (1992)