This work presents the results of studying the electrophysical properties of the YCu_(0.15)Mn_(0.85)O_(3)solid solution in the range of temperatures of T=26-400°C and frequency range of f=102-105 Hz.A model descr...This work presents the results of studying the electrophysical properties of the YCu_(0.15)Mn_(0.85)O_(3)solid solution in the range of temperatures of T=26-400°C and frequency range of f=102-105 Hz.A model description of the revealed dispersion of dielectric parameters in the material is made.The nonclassical modified Havriliak-Negami model written for complex electrical conduc-tivity was used as an approximation model.It is shown that the application of this model almost exactly describes the frequency behavior of the dielectric constantε′/ε0(f),the dielectric loss tangent tgδ(f)as well as the real and imaginary parts of complex conductivityγ′(f)andγ′′(f).The results of this work are an important step in identifying the opportunities and understanding the applications of this model.展开更多
In this paper,we report the successful growth of 0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)/SrTiO_(3)/Si(001)heterostructure using RFcathode sputtering in an oxygen atmosphere.The deposited films have been investigated b...In this paper,we report the successful growth of 0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)/SrTiO_(3)/Si(001)heterostructure using RFcathode sputtering in an oxygen atmosphere.The deposited films have been investigated by X-ray diffractometry and spectroscopic ellip-sometry(SE).0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)films on silicon substrates with a strontium titanate buffer layer are single-phase,polycrystalline with a texture in the 001 direction.The unit cell parameters calculated in the tetragonal approximation were c=4.005±0.001Å;a=3.995±0.001Å.The presence in the films of small unit cell deformation arising from different unit cells parameters of the film and substrate is observed.Dielectric properties and capacitance-voltage characteristics have been measured.The ellipsometric parameters have been obtained.展开更多
The paper discusses the features of the effect of modification with lithium carbonate on the dielectric dispersion of lead ferroniobate ceramics.The modifier has been previously shown to change the ways of the recryst...The paper discusses the features of the effect of modification with lithium carbonate on the dielectric dispersion of lead ferroniobate ceramics.The modifier has been previously shown to change the ways of the recrystallization sintering and therefore reduce the sintering temperature of the ceramics,increase their average grain size,and improve their dielectric and piezoelectric properties.In this study,the emphasis is placed on the analysis of the diffusion effects of the ferroelectric phase transition upon such mod-ification considered from the standpoint of the chemical specifics of the modifier and its location in the structure of the parent compound.展开更多
The research findings of the phase composition,nanostructure and optical properties of strontium-barium niobate thin films are discussed.Sr_(x)Ba_(1−x)Nb_(2)O_(6)nanosized films(x=0.5 and 0.61)were characterized by XR...The research findings of the phase composition,nanostructure and optical properties of strontium-barium niobate thin films are discussed.Sr_(x)Ba_(1−x)Nb_(2)O_(6)nanosized films(x=0.5 and 0.61)were characterized by XRD,SEM and AFM studies.Reflective multi-angle ellipsometry and spectrophotometry were used to determine the optical parameters(refractive index,its dispersion,and thickness of the damaged surface layer)of thin films.It was shown that SBN-50 and SBN-61 thin films were grown c-oriented on Al_(2)O_(3)(0001)and heteroepitaxial on MgO(001)substrates.The increase of refractive index,approaching its maximum value in the bulk material for a given composition as the film thickness increases,is observed.展开更多
This paper studies the dielectric spectra of solid solutions(SS)of the system(1−x−y)NaNbO_(3)-xKNbO_(3)-yCdNb_(2)O_(6) y=0.075,x=0.05÷0.30 in the temperature range(10÷900)K.The formation of a local maximum w...This paper studies the dielectric spectra of solid solutions(SS)of the system(1−x−y)NaNbO_(3)-xKNbO_(3)-yCdNb_(2)O_(6) y=0.075,x=0.05÷0.30 in the temperature range(10÷900)K.The formation of a local maximum was established in the interval(260÷300)K at small x values,which,as KNbO3 increases,is gradually blurred and becomes an inflection point.Detected in SS with x=0.05÷0.10,the shift of the maxima of dependencesε′/ε_(0)(T)andε″/ε_(0)(T),depending on the frequency of the electric field at the temperature ranges(300÷304)K and(258÷271)K,is not related to relaxation.This anomaly may indicate a crystallographic disorder to A and B positions.The conclusion is made about the expediency of using the obtained results for the development of functional ferroactive materials.展开更多
基金The work was conducted within the State assignment of SSC RAS(Project Nos.01201354240 and 01201354247).
文摘This work presents the results of studying the electrophysical properties of the YCu_(0.15)Mn_(0.85)O_(3)solid solution in the range of temperatures of T=26-400°C and frequency range of f=102-105 Hz.A model description of the revealed dispersion of dielectric parameters in the material is made.The nonclassical modified Havriliak-Negami model written for complex electrical conduc-tivity was used as an approximation model.It is shown that the application of this model almost exactly describes the frequency behavior of the dielectric constantε′/ε0(f),the dielectric loss tangent tgδ(f)as well as the real and imaginary parts of complex conductivityγ′(f)andγ′′(f).The results of this work are an important step in identifying the opportunities and understanding the applications of this model.
基金The study was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation(State task in the field of scientific activity,scientific project No.(0852-2020-0032)/(BAZ0110/20-3-07IF)).
文摘In this paper,we report the successful growth of 0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)/SrTiO_(3)/Si(001)heterostructure using RFcathode sputtering in an oxygen atmosphere.The deposited films have been investigated by X-ray diffractometry and spectroscopic ellip-sometry(SE).0.5BiFeO_(3)-0.5PbFe_(0.5)Nb_(0.5)O_(3)films on silicon substrates with a strontium titanate buffer layer are single-phase,polycrystalline with a texture in the 001 direction.The unit cell parameters calculated in the tetragonal approximation were c=4.005±0.001Å;a=3.995±0.001Å.The presence in the films of small unit cell deformation arising from different unit cells parameters of the film and substrate is observed.Dielectric properties and capacitance-voltage characteristics have been measured.The ellipsometric parameters have been obtained.
基金This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation:State Task in the Field of Scientific Activity,Scientific Project No.0852-2020-0032(BAZ0110/20-3-07IF).
文摘The paper discusses the features of the effect of modification with lithium carbonate on the dielectric dispersion of lead ferroniobate ceramics.The modifier has been previously shown to change the ways of the recrystallization sintering and therefore reduce the sintering temperature of the ceramics,increase their average grain size,and improve their dielectric and piezoelectric properties.In this study,the emphasis is placed on the analysis of the diffusion effects of the ferroelectric phase transition upon such mod-ification considered from the standpoint of the chemical specifics of the modifier and its location in the structure of the parent compound.
基金The authors are grateful to V.B.Shirokov for conducting studies of the films surface by the AFM method.This work was carried out within the framework of the State Assignment of the SSC RAS(Theme of State Registration No.01201354247).
文摘The research findings of the phase composition,nanostructure and optical properties of strontium-barium niobate thin films are discussed.Sr_(x)Ba_(1−x)Nb_(2)O_(6)nanosized films(x=0.5 and 0.61)were characterized by XRD,SEM and AFM studies.Reflective multi-angle ellipsometry and spectrophotometry were used to determine the optical parameters(refractive index,its dispersion,and thickness of the damaged surface layer)of thin films.It was shown that SBN-50 and SBN-61 thin films were grown c-oriented on Al_(2)O_(3)(0001)and heteroepitaxial on MgO(001)substrates.The increase of refractive index,approaching its maximum value in the bulk material for a given composition as the film thickness increases,is observed.
基金The research was supported by the Strategic Academic Leadership Program of the Southern Federal University(“Priority 2030”)This report is presented at the 10th Anniversary International Conference on“Physics and Mechanics of New Materials and Their Applications”(PHENMA 2021),Divnomorsk,Russia,May 23-27,2022.
文摘This paper studies the dielectric spectra of solid solutions(SS)of the system(1−x−y)NaNbO_(3)-xKNbO_(3)-yCdNb_(2)O_(6) y=0.075,x=0.05÷0.30 in the temperature range(10÷900)K.The formation of a local maximum was established in the interval(260÷300)K at small x values,which,as KNbO3 increases,is gradually blurred and becomes an inflection point.Detected in SS with x=0.05÷0.10,the shift of the maxima of dependencesε′/ε_(0)(T)andε″/ε_(0)(T),depending on the frequency of the electric field at the temperature ranges(300÷304)K and(258÷271)K,is not related to relaxation.This anomaly may indicate a crystallographic disorder to A and B positions.The conclusion is made about the expediency of using the obtained results for the development of functional ferroactive materials.
