The local cationic configurations in the K₂Sr₄Nb₁₀O₃₀ lattice and peculiarities of its surface piezoresponse

ABSTRACT

Basing on the X-ray diffraction studies, a possibility of six local cationic configurations was established for K₂Sr₄Nb₁₀O₃₀ (KSN) having a tetragonal tungsten bronze-type structure. The association of these locally charged configurations may lead to the formation of the electrically active nanoregions. The piezoresponse force microscopy studies revealed at the KSN surface the presence of a subsystem of nano- or meso-size regions, which may be electrically active. Distribution and reference size of these regions have been estimated using the Fourier filtering of the source piezoresponse image.

KEYWORDS:

• Tetragonal tungsten bronze
• K₂Sr₄Nb₁₀O₃₀
• cationic distribution
• X-ray diffraction
• piezoresponse force microscopy

Funding

This work was supported by the Ministry of Education and Science of the Russian Federation (project № 3.1649.2017/4.6) and by the University of Macau under Research & Development Grant for Chair Professor No RDG007/FST-CHD/2012.