Abstract

The photorefractive transport models that include hot-electron transport nonlinearities in the photorefractive transport equations introduce a new phase-shift mechanism that explains the large energy exchange recently observed in semi-insulating multiple-quantum-well structures during photorefractive beam coupling. We show that carrier heating by large applied electric fields contributes a nonlinear transport length that limits the magnitude of the space-charge electric field and introduces a photorefractive phase shift that can approach π/2. The nonlinear contribution is dependent on field strength and on fringe spacing and should be a general property of velocity saturation in the direct-gap semiconductors. These results may force a reinterpretation of apparent trap-limited behavior in bulk photorefractive semiconductors even under nonresonant excitation.

© 1994 Optical Society of America

Photorefractive quantum wells: transverse Franz–Keldysh geometry

Q. Wang, R. M. Brubaker, D. D. Nolte, and M.R. Melloch
J. Opt. Soc. Am. B 9(9) 1626-1641 (1992)

Photorefractive phase shift induced by nonlinear electronic transport

Q. N. Wang, R. M. Brubaker, and D. D. Nolte
Opt. Lett. 19(11) 822-824 (1994)

Role of physical parameters on the photorefractive performance of semiconductor multiple quantum wells

L. F. Magaña, F. Agulló-López, and M. Carrascosa
J. Opt. Soc. Am. B 11(9) 1651-1654 (1994)

Theory of the photorefractive effect for multiple-quantum-well structures in perpendicular field reflection grating geometry

V. V. Shkunov and M. V. Zolotarev
J. Opt. Soc. Am. B 12(5) 913-920 (1995)

Hot-carrier-transport-governed nonresonant optical nonlinearity: transient Gunn-domain grating

L. Subačius, E. Starikov, P. Shiktorov, V. Gružinskis, and K. Jarašiu̅nas
J. Opt. Soc. Am. B 15(7) 2045-2056 (1998)