Nanoscale physics

Influence of the amplitude of a high-frequency electric field on the formation of ferroelectric regular domain structures
O.Yu. Mazur, L.I. Stefanovich
Institute of Physics for Mining Processes, Nat. Acad. of Sci .of Ukraine. Simferopolska street, 2a, Dnipro-49005, Ukraine. 
E-mail: o.yu.mazur@gmail.com

The development of innovative methods for generating ferroelectric regular domain structures (RDS) of the micron and submicron periods is one of the most important tasks of modern domain engineering. One of the promising directions in this area is the study of the process of self-organized formation of RDS, when the sample is in strongly nonequilibrium conditions. Such conditions can be created by laser heating or rapid quenching of a sample from the paraphase to the ferroelectric phase.
In the framework of the Ginzburg-Landau model within the statistical approach the model for describing the kinetics of ordering of the domain structure formed in the result of quenching the sample from the paraphrase to the ferroelectric phase was developed. Lithium tantalate crystal, that undergo the second order phase transition of the order-disorder type was chosen as an example. Earlier it was shown that the process of self-organized formation of RDS is possible when a high-frequency electric field is applied to a quenched sample in the form of a monochromatic plane-polarized standing wave with a frequency above a certain critical value [1]. However, the need to use high frequencies to get a small period of structure presents some technological difficulties.
Therefore, an analysis of the ordering of the system as a function of the amplitude of the electric field was made. It is shown that such a process also has a threshold character. It turned out that RDS are formed only when the amplitude of the high-frequency external electric field superimposed on the sample does not exceed a certain critical value. This value for a lithium tantalate crystal is Еcr = 1,26106 V/m.
It seems that the results of our theoretical studies can be used in practice to obtain domain structures of the required type, including the RDS of the micron and nanoscale period.

1.	Stefanovich L.I., Mazur O.Yu. The Formation of Regular Domain Structures in Ferroelectrics under Switching Polarization in High-nonequilibrium Conditions // Journal of Nano- and Electronic Physics.-2017.-9(2).-P. 02032.