Authors: Anna N. Morozovska | Eugene А. Eliseev | Igor V. Fesych | Yuriy O. Zagorodniy | Oleksandr S. Pylypchuk | Evgen Leonenko | Maxim Rallev | Andrii D. Yaremkevych | Lesya P. Yurchenko | Lesya Demchenko | Sergei V. Kalinin | Olena Fesenko
Source: Physical review. B./Physical review. B (article, 2024-12-23)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Reentrant polar phase induced by the ferroionic coupling in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">B</mml:mi><mml:msub><mml:mi mathvariant="normal">i</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>−</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub><mml:mi mathvariant="normal">S</mml:mi><mml:msub><mml:mi mathvariant="normal">m</mml:mi><mml:mi>x</mml:mi></mml:msub><mml:mi>Fe</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math> nanoparticles Using the model of four sublattices, the Landau-Ginzburg-Devonshire-Kittel phenomenological approach and the Stephenson-Highland ionic adsorption model for the description of coupled polar and antipolar long-range orders in ferroics, we analytically calculated the phase diagrams and polar properties of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mi mathvariant="normal">B</a:mi><a:msub><a:mi mathvariant="normal">i</a:mi><a:mrow><a:mn>1</a:mn><a:mo>−</a:mo><a:mi>x</a:mi></a:mrow></a:msub><a:mi mathvariant="normal">S</a:mi><a:msub><a:mi mathvariant="normal">m</a:mi><a:mi>x</a:mi></a:msub><a:mi>Fe</a:mi><a:msub><a:mi mathvariant="normal">O</a:mi><a:mn>3</a:mn></a:msub></a:mrow></a:math> nanoparticles covered by surface ions with dependence on their size, surface ions density, samarium content <g:math xmlns:g="http://www.w3.org/1998/Math/MathML"><g:mi>x</g:mi></g:math>, and temperature. The size effects and ferroionic coupling govern the appearance and stability conditions of the long-range ordered ferroelectric, reentrant ferrielectric, and antiferroelectric phases in <h:math xmlns:h="http://www.w3.org/1998/Math/MathML"><h:mrow><h:mi mathvariant="normal">B</h:mi><h:msub><h:mi mathvariant="normal">i</h:mi><h:mrow><h:mn>1</h:mn><h:mo>−</h:mo><h:mi>x</h:mi></h:mrow></h:msub><h:mi mathvariant="normal">S</h:mi><h:msub><h:mi mathvariant="normal">m</h:mi><h:mi>x</h:mi></h:msub><h:mi>Fe</h:mi><h:msub><h:mi mathvariant="normal">O</h:mi><h:mn>3</h:mn></h:msub></h:mrow></h:math> nanoparticles. Calculated phase diagrams are in qualitative agreement with the x-ray diffraction phase analysis, electron paramagnetic resonance, infrared spectroscopy, and electrophysical measurements of <n:math xmlns:n="http://www.w3.org/1998/Math/MathML"><n:mrow><n:mi mathvariant="normal">B</n:mi><n:msub><n:mi mathvariant="normal">i</n:mi><n:mrow><n:mn>1</n:mn><n:mo>−</n:mo><n:mi>x</n:mi></n:mrow></n:msub><n:mi mathvariant="normal">S</n:mi><n:msub><n:mi mathvariant="normal">m</n:mi><n:mi>x</n:mi></n:msub><n:mi>Fe</n:mi><n:msub><n:mi mathvariant="normal">O</n:mi><n:mn>3</n:mn></n:msub></n:mrow></n:math> nanopowders sintered by the solution combustion method. The combined theoretical-experimental approach allows us to explain the influence of the ferroionic coupling and size effects in <t:math xmlns:t="http://www.w3.org/1998/Math/MathML"><t:mrow><t:mi mathvariant="normal">B</t:mi><t:msub><t:mi mathvariant="normal">i</t:mi><t:mrow><t:mn>1</t:mn><t:mo>−</t:mo><t:mi>x</t:mi></t:mrow></t:msub><t:mi mathvariant="normal">S</t:mi><t:msub><t:mi mathvariant="normal">m</t:mi><t:mi>x</t:mi></t:msub><t:mi>Fe</t:mi><t:msub><t:mi mathvariant="normal">O</t:mi><t:mn>3</t:mn></t:msub></t:mrow></t:math> nanoparticles on their polar properties. Published by the American Physical Society 2024 Ferroelectricity ; Coupling (piping) ; Polar ; Physics ; Crystallography ; Materials science ; Chemistry ; Quantum mechanics ; Dielectric Multiferroics and related materials ; Ferroelectric and Piezoelectric Materials ; Dielectric properties of ceramics