相关论文: Correlation between surface rumpling and structura…

We report investigation of structural phase transitions in technologically important material sodium niobate as a function of temperature on heating over 300-1075 K. Our high resolution powder neutron diffraction data show variety of…

We have made simultaneous torsional oscillator and transverse NMR measurements (at 165 kHz) on 3He contained within aerogels with nominal densities of 1% and 2% of solid glass. The superfluid transition is seen simultaneously by both…

A phenomenological theory has been proposed for the diffusionless structural phase transitions in crystalline solids here. It has been found that for BaTiO3 single crystal, both the phase transitions and the crystal structures can be…

X-ray diffraction studies showed that the structure of (Sr$_{1-x}$Pr$_x$)TiO$_3$ solid solutions at 300 K changes from the cubic $Pm3m$ to the tetragonal $I4/mcm$ with increasing $x$. The analysis of XANES and EXAFS spectra of the solid…

It has been known for a long time that the low temperature behavior shown by the dielectric constant of quantum paraelectric $SrTiO_{3}$ can not be fitted properly by Barrett's formula using a single zero point energy or saturation…

We report the temperature-dependent complex dielectric function of pristine bulk SrTiO$_3$ between 4.2 and 300 K within the energy range of 0.6-6.5 eV determined by spectroscopic ellipsometry. Fundamental indirect and direct band-gap…

SrPt$_2$As$_2$ single crystals with CaBe$_2$Ge$_2$-type structure were synthesized by self-melting technique. X-ray diffraction, transmission electron microscopy, electrical resistivity, specific heat and optical spectroscopy measurements…

Using first principles calculations, we determined the epitaxial-strain dependence of the ground state of the 1:1 SrCrO$_3$/SrTiO$_3$ superlattice. The superlattice layering leads to significant changes in the electronic states near the…

In the quest of understanding significant variations in the physical, chemical and electronic properties of the novel functional materials, low temperature Synchrotron X-ray Diffraction (LT-SXRD) measurements on CTO (a type-II) and CMTO (a…

Single crystals of thallium-based cuprates with the general formula Tl$_{2}$Ba$_{2}$Ca$_{n-1}$Cu$_{n}$O$_{x}$(n=1,2,3) have been grown by the flux method. The superconducting transition temperatures determined by the ac magnetic…

Temperature dependent measurements of the resistivity on RuIn$_3$ single crystals show a semiconducting behaviour, in contrast to previously published results. In the high temperature range the semiconducting gap was measured to be…

Epitaxial Ba0.5Sr0.5TiO3 thin films were prepared on Nb-doped SrTiO3 (100)substrates by the pulsed laser deposition technique, and were studied by measuring the Ti 2p - 3d resonant photoemission spectra in the valence-band region as a…

Effect of biaxial tensile strains on optical functions and band edge transitions of ultra thin epitaxial films was studied using as an example a 13 nm thick SrTiO3 films deposited on KTaO3(100) single-crystal substrates. Optical functions…

Two novel room-temperature phase transitions are observed, via synchrotron x-ray diffraction and Raman spectroscopy, in the Pb(Zr0.52Ti0.48)O3 alloy under hydrostatic pressures up to 16 GPa. A monoclinic (M)-to-rhombohedral (R1) phase…

Crystal structure, thermal and magnetic properties were systematically studied in the Y$_{1-x}$Pr$_x$CrO$_3$ with $0 \leq x \leq 0.3$ compositions. Magnetic susceptibility and specific heat measurements show an increase of the…

The compound SrNi$_2$P$_2$ can exhibit multiple crystal structures with no P-P pairs bonded (uncollapsed tetragonal, or ucT, state), with one-third of the P-P pairs bonded (one-third collapsed orthorhombic, or tcO, state), or with all P-P…

Recent experiments in the original cuprate high temperature superconductor, La$_2-x$Ba$_x$CuO$_4$, have revealed a remarkable sequence of transitions [1]. Here we investigate such crystals with Kerr effect which is sensitive to…

We studied the resonant diffraction signal from stepped surfaces of SrTiO3 at the Ti 2p -> 3d (L2,3) resonance in comparison with x-ray absorption (XAS) and specular reflectivity data. The steps on the surface form an artificial…

Neutron diffraction experiments of TmFeO$_3$ single crystals were performed in the external magnetic fields. The field along $c$-axis increases temperature of spin-reorientation transition $T_{SR}$ from phase ${\Gamma}4$ to ${\Gamma}2$.…

Temperature dependent measurements of 57Fe Mossbauer spectra on CaFe2As2 single crystals in the tetragonal and collapsed tetragonal phases are reported. Clear features in the temperature dependencies of the isomer shift, relative spectra…