The response of photorefractive crystals with bulk photovoltaic charge transport is usually highly nonlinear, and for illumination with a sinusoidal light pattern the recorded space-charge gratings possess, apart from the principal spatial frequency K, several higher spatial harmonics, 2K, 3K, etc. We show experimentally that purely sinusoidal index gratings can be recorded in LiNbO3:Fe when the charge redistribution is governed by spatially oscillating photovoltaic currents. This property is especially beneficial for holographic data storage.
© 2006 Optical Society of America
Original Manuscript: August 16, 2005
Revised Manuscript: October 21, 2005
Manuscript Accepted: October 21, 2005
Alexandr Shumelyuk, Ulrich Hartwig, Karsten Buse, Serguey Odoulov, and Theo Woike, "Linearity of index grating recording with spatially oscillating photovoltaic currents," J. Opt. Soc. Am. B 23, 857-860 (2006)