The comparative analysis of the dielectric properties of bismuth-containing pyrochlores with different manifestation of atomic order/disorder was carried out.We examined the dielectric properties(including behavior in...The comparative analysis of the dielectric properties of bismuth-containing pyrochlores with different manifestation of atomic order/disorder was carried out.We examined the dielectric properties(including behavior in electric fields)of two pyrochlore compounds:BZN(presumably a composition close to Bi_(1.5)Zn_(0.5)Nb_(1.5)O_(6.5))ceramics with chemical disorder in both A and B cation sublattices and Bi_(2)Ti_(2)O_(7)single crystal with fully chemical ordered structure.The fundamental differences between the dielectric properties of the BZN ceramics and Bi_(2)Ti_(2)O_(7)single crystal were shown.In particular,in the dielectric relaxation behavior(which cannot be described via Arrhenius law in the Bi_(2)Ti_(2)O_(7))or in the influence of the electric fields on the dielectric permittivity(split-ting of the field-cooled and zero-field-cooled behaviors was observed for Bi_(2)Ti_(2)O_(7)below estimated freezing temperature).The results of this study highlights the special role of Bi_(2)Ti_(2)O_(7)as a candidate material for studying aspects of geometric frustration related with pyrochlore structure in non-magnetic medium and specifies the future directions of research.展开更多
The electromechanical responses of multicomponent solid solutions Pb_(0.95)Ba_(0.05)(Mg_(1/3)Nb_(2/3))_(0.471)(Zn_(1/3)Nb_(2/3))_(0.102)(Ni_(1/3)Nb_(2/3))_(0.152)Ti_(0.275)O_(3)in low and high electric fields were stu...The electromechanical responses of multicomponent solid solutions Pb_(0.95)Ba_(0.05)(Mg_(1/3)Nb_(2/3))_(0.471)(Zn_(1/3)Nb_(2/3))_(0.102)(Ni_(1/3)Nb_(2/3))_(0.152)Ti_(0.275)O_(3)in low and high electric fields were studied.In both cases,significant electromechanical responses are observed.In particular,the maximum values of the large-signal piezoelectric coefficient d_(33)reach 1600 m/V at very low values of the electric field(≈5 kV/cm).The observed features of the electromechanical responses of the studied ceramics are advantages in terms of their possible application in actuators.展开更多
基金The authors are grateful to L.A.Shilkina for X-ray phase analysis of the BZN samples.The reported study was funded by Russian Science Foundation(RSF)-research projects no.20-72-00086(BZN ceramics preparation,dielectric mea-surements)At RTU MIREA,the work was supported by the Ministry of Science and Higher Education of Russia(project FSFZ 0706-2020-2022,Bi2Ti2O7 single crystal growth),the equipment of the Center for Collective Use of RTU MIREA was used.
文摘The comparative analysis of the dielectric properties of bismuth-containing pyrochlores with different manifestation of atomic order/disorder was carried out.We examined the dielectric properties(including behavior in electric fields)of two pyrochlore compounds:BZN(presumably a composition close to Bi_(1.5)Zn_(0.5)Nb_(1.5)O_(6.5))ceramics with chemical disorder in both A and B cation sublattices and Bi_(2)Ti_(2)O_(7)single crystal with fully chemical ordered structure.The fundamental differences between the dielectric properties of the BZN ceramics and Bi_(2)Ti_(2)O_(7)single crystal were shown.In particular,in the dielectric relaxation behavior(which cannot be described via Arrhenius law in the Bi_(2)Ti_(2)O_(7))or in the influence of the electric fields on the dielectric permittivity(split-ting of the field-cooled and zero-field-cooled behaviors was observed for Bi_(2)Ti_(2)O_(7)below estimated freezing temperature).The results of this study highlights the special role of Bi_(2)Ti_(2)O_(7)as a candidate material for studying aspects of geometric frustration related with pyrochlore structure in non-magnetic medium and specifies the future directions of research.
基金The electromechanical measurements were performed using the equipment of the Shared Research Facility Centre of SFedU,Research Institute of Physics.This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation(State assignment in the field of scientific activity,Southern Federal University,2020).
文摘The electromechanical responses of multicomponent solid solutions Pb_(0.95)Ba_(0.05)(Mg_(1/3)Nb_(2/3))_(0.471)(Zn_(1/3)Nb_(2/3))_(0.102)(Ni_(1/3)Nb_(2/3))_(0.152)Ti_(0.275)O_(3)in low and high electric fields were studied.In both cases,significant electromechanical responses are observed.In particular,the maximum values of the large-signal piezoelectric coefficient d_(33)reach 1600 m/V at very low values of the electric field(≈5 kV/cm).The observed features of the electromechanical responses of the studied ceramics are advantages in terms of their possible application in actuators.
