title: High-temperature-recorded index gratings in periodically poled lithium niobate.
abstract: Holographic index gratings based on a zero-electric-field photorefractive effect are recorded at high temperatures in copper-doped periodically poled lithium niobate crystals. The interplay between the domain structure and the index grating is studied: the fundamental grating with spatial frequency K is strongly suppressed. Pronounced sideband gratings with K(s)=K+sG appear, where G is the domain grating vector and s is an integer number. After development, an additional grating based on the electro-optic effect shows up. In contrast with the previously mentioned gratings, this grating allows anisotropic diffraction.
authors.affiliation: Institute of Physics, University of Bonn, D-53115 Bonn, Germany. hartwig@uni-bonn.de
authors.forename: U
authors.initials: U
authors.lastname: Hartwig
authors.forename: M
authors.initials: M
authors.lastname: Kösters
authors.forename: Th
authors.initials: T
authors.lastname: Woike
authors.forename: K
authors.initials: K
authors.lastname: Buse