相关论文: Observation of quasi-elastic light scattering in B…
We measured the temperature dependence of low-frequency Raman spectra in Li$_2$RuO$_3$, and observed multipeak quasielastic scattering in the Ru honeycomb polarizations below and above the magnetostructural transition temperature. We…
We have measured temperature dependence of low-frequency Raman spectra in CuGeO$_3$, and have observed the quasi-elastic scattering in the $(c,c)$ polarization above the spin-Peierls transition temperature. We attribute it to the…
We present an experimental study of the quasi-elastic Raman scattering (QES) of plane-wave and twisted light by liquid crystals. Depending on their temperature, these crystals can exhibit isotropic, nematic and chiral nematic phases. The…
In-plane temperature dependent dielectric behavior of BiFeO3 (BFO) as-grown thin films show diffuse but prominent phase transitions near 450 (+/-10) K and 550 K with dielectric loss temperature dependences that suggest skin layer effects.…
The low-energy part of the vibration spectrum in PbMg$_{1/3}$Nb$_{2/3}$O$_3$ (PMN) relaxor ferroelectric has been studied by neutron scattering above and below the Burns temperature, T$_d$. The transverse acoustic and the lowest transverse…
Inelastic light scattering spectra of Bi_2Se_3 and Sb_2Te_3 single crystals have been measured over the temperature range from 5 K to 300 K. The temperature dependence of dominant A^{2}_{1g} phonons shows similar behavior in both materials.…
Surface Quasi-Elastic Light Scattering (SQELS) is an application of dynamic light scattering to measure the dynamics of the thermal roughness of liquid surfaces. An analysis of the spectrum of thermal fluctuations provides information on…
Knowledge of the electronic band structure of multiferroic oxides, crucial for the understanding and tuning of photo-induced effects, remains very limited even in the model and thoroughly studied BiFeO3. Here, we investigate the electronic…
Our measured dielectric constant and mechanical response of multiferroic BiFeO3 indicate four phase transitions below room temperature. Features correlate with those reported at 50K (from a peak in the zero-field-cooled magnetic…
We present neutron inelastic scattering measurements of the low-energy phonons in single crystal BiFeO3. The dispersions of the three acoustic phonon modes (LA along [100], TA1 along [010] and TA2 along [110]) and two low energy optic…
We report results of a comprehensive study of the phase transition at T_N (~643 K) as a function of particle size in multiferroic BiFeO3 system. We employed electrical, thermal, and temperature dependent X-ray diffraction (XRD) studies in…
Inelastic neutron scattering experiments were performed on single crystals of the heavy-fermion compound CeIn$_{3}$ for temperatures below and above the N\'eel temperature, $T_N$. In the antiferromagnetically ordered phase, well-defined…
The anisotropic optical properties of multiferroic BiFeO$_3$ thin films have been determined with Mueller matrix ellipsometry at room-temperature. The full dielectric tensors of tetragonal-like and rhombohedral-like BiFeO$_3$ phases…
We have performed Raman scattering investigations on the high energy magnetic excitations in a BiFeO$_3$ single crystal as a function of both temperature and laser excitation energy. A strong feature observed at 1250 cm$^{-1}$ in the Raman…
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 ~…
Resonant Rayleigh scattering of light from electrons confined in gallium arsenide double quantum wells displays significant changes at temperatures that are below one degree Kelvin. The Rayleigh resonance occurs for photon energies that…
Raman scattering experiments on LaFeAsO with splitted antiferromagnetic (T_AFM = 140 K) and tetragonal-orthorhombic (T_S = 155 K) transitions show a quasi-elastic peak (QEP) in B2g symmetry (2 Fe tetragonal cell) that fades away below…
Resonant inelastic light scattering experiments at $\nu=1/3$ reveal a novel splitting of the long wavelength modes in the low energy spectrum of quasiparticle excitations in the charge degree of freedom. We find a single peak at small…
Elastic light scattering by low-dimensional semiconductor objects is investigated theoretically. The differential cross section of resonant light scattering on excitons in quantum dots is calculated. The polarization and angular…
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…