Formation of Nanodomain Structure in Front of the Moving Domain Wall in Lithium Niobate Single Crystal Modified by Proton Exchange

Abstract

Formation and evolution of the bands with nanodomain structure in front of the moving domain wall were studied in proton exchanged LiNbO₃ in field range. The width of the nanodomain bands grew with field increasing. For switching in constant field three types of domain structure evolution were studied: 1) continuous growth of hexagon domains at 21.0 kV/mm, 2) formation and growth of wide domain wall at 21.5 kV/mm, 3) growth of micro- and nanodomain ensembles at 22.0 kV/mm. Discrete switching being the origin of obtained effects is caused by retardation of depolarization field screening in crystal with dielectric surface layer.

Keywords:

• Lithium niobate
• proton exchange
• surface dielectric layer
• nanodomain structure
• domain wall motion

Acknowledgments

The equipment of the Ural Center for Shared Use “Modern Nanotechnology”, Institute of Natural Sciences, Ural Federal University has been used. The research was made possible in part by RFBR (grants 10-02-96042-r-Ural-а, 10-02-00627-а, 11-02-91066-CNRS-а, and 12-02-31713-mol-a), by Ministry of Education and Science (contracts 16.552.11.7020, 14.513.12.0006) and with the financial support of young scientists in terms of Ural Federal University development program.