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Information × Registration Number 0223U003151, 0120U101192 , R & D reports Title Phase transitions induced by oxygen vacancies in oxide ferroics popup.stage_title Head Glynchuk Maya D., Доктор фізико-математичних наук Registration Date 02-04-2023 Organization Institute of Problems of Materials Science named after IM Frantsevich of the National Academy of Sciences of Ukraine popup.description2  Enhanced electromechanical response in BaTiO3 thin films was observed for the first time using dynamic local control of oxygen vacancies in force microscopy. It is shown that vacancy dynamics in complex oxides can play a key role in determining functional properties, and thus provides a new route to achieving improved ferroic response with higher functional temperature ranges in ferroelectrics and other ferroics. The technology of synthesis of single-phase ceramic samples of relaxors and nano-sized powders of binary oxides has been improved. Dielectric studies of Pb(Mg1/3Nb2/3)O3 relaxor samples with the indicated oxygen vacancies in their structure indicate the formation of two phases in the studied samples, and both phases belong to the relaxor ferroelectric. The effect of Sn on the energy storage characteristics and conductivity mechanisms of ceramics (Ba0.85Ca0.15)(Zr0.1-xSnxTi0.9)O3 (x = 0, 0.02, 0.04 and 0.06) made by sol- gel method. Significant enhancement of ferroelectricity in HfO2 thin films based on defect control by He ion bombardment has been demonstrated. Possible competing mechanisms are analyzed, including He ion-induced molar volume changes, vacancy redistribution, vacancy formation, and vacancy mobility activation. These studies reveal the origin of ferroelectricity in this system and open the way to nanoengineering binary ferroelectrics Mechanisms that can lead to stationary or transient negative capacitance in a ferroelectric film stabilized by a dielectric layer have been theoretically investigated. The effect of negative capacitance is accompanied by almost zero dielectric susceptibility in a wide range of voltages and low frequencies. These results may help clarify observations of transient negative capacitance in thin ferroelectric films. Product Description popup.authors Eliseev Evgen A Zagorodniy Yuriy О Kondakova Iryna V Krychynska Vira O Kuzian Roman O Likhtin Andrіy E Laguta Valentyn V Leshchenko Oksana V Pavlikov Viktor М Pleskach Igor V Roginets Nadiya V Stratiev Victor G Umpeleva Elizaveta D Ushakov Oleksandr M Yurchenko Lesia Р popup.nrat_date 2023-04-02 Close