Ferroelectric nanodomains

Ferroelectric Domain Breakdown Application to Nanodomain Technology... 

The major trends in ferroelectric photonic and electronic devices are based on development of materials with nanoscale features. Piezoelectric, electrooptic, nonlinear optical properties of fe are largely determined by the arrangement of ferroelectric domains. A promising way is a modification of these basic properties by means of tailoring nanodomain and refractive index superlattices. 

Nanometer scale domain configurations in fe bulk crystals pave the way for a new class of photonic devices. As an example, preliminary calculations show that a uv laser (A = 300 nm) based on second harmonic generation in LiTaC>3 crystal requires a periodic nanodomain superlattice with domain widths of around 700 nm. In addition, the current domain gratings in ferroelectric crystals are suitable only for quasi-phase-matched nonlinear interactions in the forward direction, where the pump and generated beams propagate in the same direction. Sub-micron ferroelectric domain gratings are the basis for a new family of devices based on backward nonlinear quasi-phase-matched optical interactions in which the generated beam travels in a reverse or another non-collinear direction to the incident beam. Non-collinear... 

New promising technologies for future electron-beam lithography applications based on pyroelectrically induced electron emission from LiNbOs ferroelectrics [22] were recently proposed [23], The developed system possessing micrometer scale resolution used 1 1 electron beam projection. The needed electron pattern was obtained by means of deposited micrometer-size Ti-spots on the polar face of LiNbOs. Another solution for the high resolution electron lithography may be found in nanodomain patterning of a ferroelectric template. 

The radius of string-like nanodomains observed under the fdb conditions is much smaller than its length, rm -C lm. Consequently, for the fdb phenomenon the shape invariant value should also be small. Equation (10.18) shows that the shape invariant has the lowest value if a ferroelectric material satisfies the following conditions ... 

The physical limits and technological requirements of domain dimensions for a new generation of nanodomain-based devices were considered. It was shown that for both ferroelectric thin films and crystals the achievable domain size is in the range of 100 nm. It is shown that for 100 nm thick ferroelectric films, an application of nanosize electrodes does not make a big difference compared with conventional polarization reversal setups and physical mechanism. However, in the case of bulk ferroelectrics, the use of a switching afm tip electrode for generation of long domains with a nanometer size radius requires a new approach both for polarization reversal instrumentation and physics of domain inversion. 

Shvartsman VV, KhoUdn AL, Orlova A, Kiselev D, Bogomolov AA, Sternberg A (2005) Polar nanodomains and local ferroelectric phenomena in relaxor lead lanthanum zirconate titanate ceramics. Appl Phys Lett 86 202937... 

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