The coexistence of ferroelectricity,conductivity,and magnetism in a single-phase material has attracted considerable attention due to fundamental interest and tremendous technological potential.However,their mutually ...The coexistence of ferroelectricity,conductivity,and magnetism in a single-phase material has attracted considerable attention due to fundamental interest and tremendous technological potential.However,their mutually exclusive mechanisms hinder the discovery of multifunctional conducting multiferroics.Here,we propose a new material design approach for electron engineering to enable these conflicting properties to coexist.We use first principles calculations to demonstrate that appropriate mechanical strain can turn the excess electrons in doped BaTiO_(3) from a free-carrier configuration to a localized polaronic state by modulating the electron–phonon coupling.The resulting localized spin-polarized electron survives the host ferroelectricity and consequently manifests as a multiferroic polaron.The multiferroic properties coexist with the electronic conductivity arising from the highhopping mobility of the polaron,which enables the doped epitaxial BaTiO_(3) to act as a multiferroic conducting material.This mechanical control over the electron configuration is a potential path toward unusual coexisting properties.展开更多
基金The authors acknowledge the financial support for T.X.by the National Natural Science Foundation of China(Grant no.11802169)for T.S.and T.K.by JSPS KAKENHI(25000012,26289006,15K13831,and 17H03145)for J.W.by the Fundamental Research Funds for the Central Universities 2018XZZX001-05,and for T.Y.Z.by the 111 project(No.D16002)from the State Administration of Foreign Experts Affairs and the Ministry of Education,PRC.
文摘The coexistence of ferroelectricity,conductivity,and magnetism in a single-phase material has attracted considerable attention due to fundamental interest and tremendous technological potential.However,their mutually exclusive mechanisms hinder the discovery of multifunctional conducting multiferroics.Here,we propose a new material design approach for electron engineering to enable these conflicting properties to coexist.We use first principles calculations to demonstrate that appropriate mechanical strain can turn the excess electrons in doped BaTiO_(3) from a free-carrier configuration to a localized polaronic state by modulating the electron–phonon coupling.The resulting localized spin-polarized electron survives the host ferroelectricity and consequently manifests as a multiferroic polaron.The multiferroic properties coexist with the electronic conductivity arising from the highhopping mobility of the polaron,which enables the doped epitaxial BaTiO_(3) to act as a multiferroic conducting material.This mechanical control over the electron configuration is a potential path toward unusual coexisting properties.
