519 research outputs found
Modeling of micro- and nano-scale domain recording by high-voltage atomic force microscopy in ferroelectrics-semiconductors
The equilibrium sizes of micro- and nano-domains caused by electric field of
atomic force microscope tip in ferroelectric semiconductor crystals have been
calculated. The domain was considered as a prolate semi-ellipsoid with rather
thin domain walls. For the first time we modified the Landauer model allowing
for semiconductor properties of the sample and the surface energy of the domain
butt. The free carriers inside the crystal lead to the formation of the
screening layer around the domain, which partially shields its interior from
the depolarization field. We expressed the radius and length of the domain
though the crystal material parameters (screening radius, spontaneous
polarization value, dielectric permittivity tensor) and atomic force microscope
tip characteristics (charge, radius of curvature). The obtained dependence of
domain radius via applied voltage is in a good quantitative agreement with the
ones of submicron ferroelectric domains recorded by high-voltage atomic force
and scanning probe microscopy in LiNbO3 and LiTaO3 crystals.Comment: 21 pages, 5 figure
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