相关论文: High-temperature structural phase transition and i…

Single phase polycrystalline sample of perovskite Sr2TiMnO6 (STMO) has been successfully synthesized via solid state reaction route. Its detailed structural and physical properties have been studied using x-ray diffraction, transmission…

Polarized Raman scattering spectra of superconducting K$_x$Fe$_{2-y}$Se$_2$ and nonsuperconducting K$_{0.8}$Fe$_{1.8}$Co$_{0.2}$Se$_2$ single crystals were measured in a temperature range from 10 K up to 300 K. Two Raman active modes from…

The doping dependence of the micro-Raman spectra of high quality La_{2-x}Sr_xCuO_4 microcrystals with x=0.0-0.45 has been investigated in the region 10-300 K. The phonon at ~100 cm^{-1} of the orthorhombic phase shows a classical soft mode…

In this paper, we present the spin-phonon coupling and dielectric response of nano-crystalline Pr$_2$CoMnO$_6$ employing Raman and dielectric spectroscopic study. Pr$_2$CoMnO$_6$ is a manganite compound , it undergoes a paramagnetic to…

Polarized infrared reflectivity spectra of a (110)-oriented TbScO3 single crystal plate were measured down to 10 K. The number of observed polar phonons active along the crystallographic c axis at low temperatures is much higher than…

We have measured the polarized Raman scattering spectra of Cd2Re2O7, the first superconducting pyrochlore, as a function of temperature. For temperatures below the cubic-to-tetragonal structural phase transition (SPT) at 200K, a peak with…

Detailed Raman spectroscopy studies on polycrystalline Sr1-xPrxTiO3 (x=0.01, 0.025, 0.05, 0.075, 0.09, 0.13, 0.15, 0.17) samples are reported elucidating the microscopic mechanism of relaxor ferroelectrics. The polar mode was observed upto…

The sequence of phase transitions in PbHf0.83Sn0.17O3 has been studied by THz, far infrared and Raman spectroscopies, revealing the complementary behaviour of both, polar and non-polar phonons and their impact on the transition lattice…

We report results of the Raman measurements for SrRu$_2$O$_6$ having extraordinary high N$\acute{\textrm{e}}$el temperature for a layered material. No additional phonon modes were detected at the temperature of magnetic transition thus…

We report $^{75}$As nuclear magnetic resonance (NMR) / nuclear quadrupole resonance (NQR) and transmission electron microscopy (TEM) studies on LaFeAsO$_{1-x}$F$_{x}$. There are two superconducting domes in this material. The first one…

Highly-strained BiFeO3 exhibits a "tetragonal-like, monoclinic" crystal structure found only in epitaxial films (with an out-of-plane lattice parameter exceeding the in-plane value by >20%). Previous work has shown that this phase is…

We report inelastic neutron scattering measurements of the phonon spectra in a pure powder sample of the multiferroic material BiFeO3. A high-temperature range was covered to unravel the changes in the phonon dynamics across the Neel (T_N ~…

A detailed temperature and pressure investigation on BiGdO$_{3}$ is carried out by means of dielectric constant, piezoelectric current, polarization-electric field loop, Raman scattering and x-ray diffraction measurements. Temperature…

Sodium niobate (NaNbO3) exhibits most complex sequence of structural phase transitions in perovskite family and therefore provides as excellent model system for understanding the mechanism of structural phase transitions. We report…

We conduct first-principles theoretical studies to investigate the temperature-dependent phonon properties of orthorhombic SrZrO$_3$ (SZO) perovskite. Our calculations include the quasiharmonic approximation, in which we explored mode…

The monoclinic double-perovskite Sr2YRuO6 has recently gained a renewed interest in order to get a deeper insight into the exotic magnetic ground states associated with geometric frustration. Striking discrepancies between the spin order…

Electronic structure of pulsed laser deposited epitaxial LaVO3 (LVO) thin film grown on LaAlO3 (001) (LAO) substrate, has been studied at room temperature and at 130 K, which is below the structural (141 K) and magnetic transition…

Recent theoretical studies [Chen et al., Phys. Rev. B 82, 174440 (2010), Ishizuka et al., Phys. Rev. B 90, 184422 (2014)] for the magnetic Mott insulator Ba2NaOsO6 have proposed a low-temperature order parameter that breaks lattice…

Reflectivity as a function of temperature for the La$_{0.67}$Ca$_{0.33}$MnO$_{3}$ (LCMO) film has been measured across the metal-insulator phase transition. The optical properties and their temperature dependence were determined in the…

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…