Using accurate band structures of InAs, InSb, and two Hg<sub>1−x</sub>Cd<sub>x</sub>Te alloys, we calculate the change in refractive index caused by the photoexcited electrons and holes. The effects of both free-carrier absorption (FCA) and one-photon absorption are considered. We find that the change in refractive index varies nonlinearly with the density of photoexcited carriers and that the generally neglected FCA contribution is significant in InAs, owing to its weak spin-orbit coupling.
© 2006 Optical Society of America
Original Manuscript: June 2, 2006
Manuscript Accepted: July 13, 2006
Z. G. Yu, Srini Krishnamurthy, and Shekhar Guha, "Photoexcited-carrier-induced refractive index change in small bandgap semiconductors," J. Opt. Soc. Am. B 23, 2356-2360 (2006)