A novel transient-grating geometry, which is nondegenerate, copropagating, phase matched, and polarization sensitive, is used to isolate and measure independently the ultrafast dynamics of multiple coexisting gratings in GaAs:EL2 with a temporal resolution of <5 psec. This technique permits the measurement of the evolution of the photorefractive grating in materials with zinc blende symmetry, where the photorefractive grating is usually obscured by the stronger free-carrier and instantaneous bound-electronic gratings.
© 1991 Optical Society of America
W. Andreas Schroeder, Thomas S. Stark, Martin D. Dawson, Thomas F. Boggess, Arthur L. Smirl, and G. C. Valley, "Picosecond separation and measurement of coexisting photorefractive, bound-electronic, and free-carrier grating dynamics in GaAs," Opt. Lett. 16, 159-161 (1991)