We report the measurement of group index and dispersion in an erbium-doped fiber amplifier by Fourier transformation of low-coherence interferograms. In a germania-codoped fiber whose background dispersion was −14 ps/(km nm) we measured resonant gain-induced changes as high as 9 and −12 ps/(km nm) near 1.536 μm. The interferometric measurements agree with calculations based on a Kramers–Kronig transformation of absorption and emission spectra.
© 1993 Optical Society of America
Robert K. Hickernell, Kazumasa Takada, Makoto Yamada, Makoto Shimizu, and Masaharu Horiguchi, "Pump-induced dispersion of erbium-doped fiber measured by Fourier-transform spectroscopy," Opt. Lett. 18, 19-21 (1993)