title: Characteristics of recording and thermal fixing in lithium niobate.
abstract: We present a theoretical model in which the band-transport equations and the coupled-wave equations are considered to study the two thermal-fixing methods (simultaneous fixing and postfixing) in Fe:LiNbO(3). We found that, in simultaneous fixing, the existing ionic-grating affects the writing of the electronic grating by reduction of the coupling gain, and the grating envelope of the fixed-index grating is quite uniform inside the photorefractive crystal in comparison with the method of postfixing. The resulting diffraction efficiency of the fixed-volume grating is dependent mainly on the initial intensity modulation of the two writing beams. A set of experiments is also presented.
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.forename: L
authors.initials: L
authors.lastname: Liu
authors.forename: L
authors.initials: L
authors.lastname: Xu