相关论文: Ferroelectricity of Li-doped silver niobate (Ag,Li…
Full pattern Le-Bail refinement using x-ray powder diffraction profiles of Sr1-xCaxTiO3 for x=0.02, 0.04 in the temperature range 12 to 300 K reveals anomalies in the unit cell parameters at 170, 225 K due to an antiferrodistortive (cubic…
We report on the lattice evolution of BiFeO3 as function of temperature using far infrared emissivity, reflectivity, and X-ray absorption local structure. A power law fit to the lowest frequency soft phonon in the magnetic ordered phase…
Temperature evolution of dielectric response, atomic structure, and lattice dynamics in thin film of sodium niobate in the epitaxial NaNbO$_3$/SrRuO$_3$/(001)MgO heterostructure is studied by dielectric measurements, x-ray diffraction, and…
Sodium niobate, a lead-free ferroic material, hosts delicately-balanced, competing order parameters, including ferroelectric states that can be stabilized by epitaxial strain. Here, we show that the resulting macroscopic ferroelectricity…
We present here the results of frequency dependent dielectric, polarization and powder X-ray powder diffraction studies in the 300 to 100K temperature range for Ba_0.55Sr_0.45TiO_3. The dielectric results indicate a succession of three…
Polarization dynamics and domain structure evolution in ferroelectric Al$_{0.93}$B$_{0.07}$N are studied using piezoresponse force microscopy and spectroscopies in ambient and controlled atmosphere environments. The application of negative…
We report a model describing the molecular orientation disorder in CH3NH3PbI3, solving a classical Hamiltonian parametrised with electronic structure calculations, with the nature of the motions informed by ab-initio molecular dynamics. We…
The polarized Raman spectra of orthorhombic RMnO3 series (R=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Y) were studied at room temperature. The variation of phonon frequencies with R ionic radius rR as a whole confirms the commonly accepted Raman line…
A previously unreported ferroelectric phase has been revealed on a highly homogeneous sample of Pb(Zr0.52Ti0.48)O3 by high-resolution synchrotron x-ray powder diffraction measurements. At ambient temperature the sample has tetragonal…
Metals cannot exhibit ferroelectricity because static internal electric fields are screened by conduction electrons, but in 1965, Anderson and Blount predicted the possibility of a ferroelectric metal, in which a ferroelectric-like…
Crystallography and dielectric properties in Dion-Jacobson layered perovskites, CsNdNb$_2$O$_7$ and RbNdNb$_2$O$_7$, have been examined in dense polycrystalline samples, and polarization hysteresis loops that substantiate ferroelectricity…
We report the phase diagram of (Ba1-xCax)(Zr0.1Ti0.9)O3 solid solution. It is found that substitution of smaller Ca ions for Ba ions can slightly increase the cubic-tetragonal(T) para-ferroelectric phase transition temperature and strongly…
For decades it has been a well-known fact that among the few ferroelectric compounds in the perovskite family namely BaTiO3, KNbO3, PbTiO3 Na1/2Bi1/2TiO3 the dielectric and piezoelectric properties of BaTiO3 is considerably higher than the…
Thermoelectric energy conversion - the exploitation of the Seebeck effect to convert waste heat into electricity - has attracted an increasing amount of research attention for energy harvesting technology. Niobium-doped strontium titanate…
Structural phase transformations of [110] electric field cooled Pb(Mg1/3Nb2/3)O3-30%PbTiO3 (PMN-30%PT) crystals have been performed by x-ray diffraction in a field-cooled (FC) condition. A phase sequence of…
Some of (1-x)NaNbO_3-(x)ABO_3 perovskite solid solutions exhibit a dramatic diffusion of the dielectric permittivity epsilon' maximum and relaxor-type behavior when the second component concentration exceeds a threshold value x_0. The…
We present a first-principles investigation of ferroelectricity in layered perovskite oxide La2Ti2O7 (LTO), one of the compounds with highest Curie temperature known (1770 K). Our calculations reveal that LTO's ferroelectric transition…
Eu modified Na1/2Bi1/2TiO3 (NBT) was investigated for electric-field induced Eu+3 photoluminescence (PL) and structural changes. Detailed analysis revealed that below a critical Eu composition electric field irreversibly suppresses the…
First-principles calculations were performed to investigate the ferroelectric properties of barium titanate and bismuth ferrite, as well as phonon dispersion of BaTiO3, using density functional theory and density functional perturbation…
In this work, the potential to exploit Aurivillius higher order composition (n=6) given by Bi4Ti3O12-3BiFeO3 as single phase and high temperature magnetoelectric materials are well explored by elaborately studying the concerned structure…