Journal of the Optical Society of America B

Resonance-enhanced refractive index and its dynamics in rare-earth-doped fibers

Yan Xue, P. L. Chu, Weiping Zhang

Published Oct 1, 1993• 16 citations

Abstract

We present a theory that enables us to account for the pump-induced change of refractive index in a rare-earth-doped fiber. Experimental results carried out on an erbium-doped fiber with cw pump and cw signal operation confirm the accuracy of this theory at the steady state. Both theoretical and experimental results show that significant index changes can be obtained for the order of 1–2 mW of cw optical pump or signal power. In addition we studied the transient dynamics of the resonance-enhanced refractive index in a wide range of pulse widths from millisecond to tens of femtoseconds. The result shows that a fast response of refractive-index changes is achievable since the effects of spontaneous emission and nonradiative decay are negligible in the short-pulse case.

DOI: 10.1364/josab.10.001840

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