Photorefractive and free-carrier nonlinearities in GaAs transfer energy from a strong picosecond pump, which is linearly polarized at an arbitrary angle to a weak s-polarized probe, into a p-polarized beam propagating in the probe direction. By placing the GaAs between a crossed pair of high-quality polarizers that are set to extinguish the probe in the absence of the pump, an efficient, high-contrast, high-speed optical switch is realized. By varying the pump–probe ratio, delay, fluence, and polarization, we can maximize the intensity of the p-polarized component. This intensity with the pump present divided by that without the pump, the on–off ratio, is approximately 2 at fluences as low as 0.03 mJ/cm2 and approaches 10,000 at fluences of 15 mJ/cm2 and pump polarizations of 45°.
© 1989 Optical Society of America
Original Manuscript: September 9, 1988
Manuscript Accepted: November 30, 1988
Published: February 15, 1989
Arthur L. Smirl, Thomas F. Boggess, George C. Valley, J. Dubard, and A. G. Cui, "Polarization-rotation switch using picosecond pulses in GaAs," Opt. Lett. 14, 242-244 (1989)