Ferroelectric domain breakdown

10 Ferroelectric Domain Breakdown Application to Nanodomain Technology 

Another method presented in this paper is the indirect eb method when the C -lace of a LiNbOs ferroelectric is preliminary coated by a highly defective layer of the amorphous photo-resist material pmma. The thickness of this dielectric layer is large enough to protect the LiNb03 from penetration of high energy electrons into the bulk. In the presented calculations and simulation a very limited number of electrons penetrated into the LiNbOs crystal, so most of the injected electron charge remains trapped in the pmma layer. 

Thus observation of ferroelectric domain reversal induced by indirect electron beam irradiation in LiNb03 bulk crystals represents a pronounced fdb effect. The reversed structure represents domain clusters consisting of multiple string-like domains with nanometer radius and 350 pm lengths. Fabricated one- and two-dimensional domain configurations could be used for a broad range of new 2-D as well as potential 3-D nonlinear photonic devices. 

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Indirect electron beam induced ferroelectric domain breakdown... 

A spherical model was used in Ref. [15] in order to obtain the shape of the domains, reversed under the fdb conditions. This model was widely applied for studies of different processes that take place in the field of afm tip (see Ref. [65]), including ferroelectric polarization reversal [66-69], In this model the field of the tip apex is supposed to coincide with a field of a metallic sphere, the radius of which is equal to the radius of curvature of the tip apex. Using a simple approximation it may be supposed that the tip charge is concentrated in the center of the sphere [15,64-69], We will take into account a more general model and check the accuracy of the simple spherical model application to the ferroelectric domain breakdown condition. 

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