相关论文: Raman evidence for Orbiton-Mediated Multiphonon Sc…

Using infrared (IR) and Raman spectroscopies combined with high-resolution x-ray diffraction, we address several controversial aspects of altermagnetic $\alpha$-MnTe. We show that mechanical stress applied to crystals of this material…

We perform thermodynamic and inelastic neutron scattering (INS) measurements to study the lattice dynamics (phonons) of a cubic collinear antiferromagnet Cu$_3$TeO$_6$ which hosts topological spin excitations (magnons). While the specific…

We report inelastic neutron scattering measurements over 7-1251 K in CaMnO3 covering various phase transitions, and over 6-150 K in PrMnO3 covering the magnetic transition. The excitations around 20 meV in CaMnO3 and at 17 meV in PrMnO3 are…

Raman and IR spectra of k-(BEDT-TTF)_2Cu[N(CN)_2]Br [BEDT-TTF denotes bis(ethylenedithiolo)tetrathiafulvalene] and its deuterated and partially deuterated analogues were measured at temperatures between 5 and 300 K and cooling rates from 1…

Neutron scattering measurements of the lowest-energy TO phonons in the relaxor Pb(Mg1/3Nb2/3)O3 (PMN) are reported for 10<=T<=750 K. The soft mode, which is overdamped by the polar nanoregions below the Burns temperature T_d = 620 K,…

Raman spectra have been measured on iron-based quaternary CeO$_{1-x}$F$_x$FeAs and LaO$_{1-x}$F$_x$FeAs with varying fluorine doping at room temperatures. A group analysis has been made to clarify the optical modes. Based on the first…

We investigate the magnetization dynamics of $TmFeO_3$ single crystals across the spin-reorientation phase transition using broadband microwave absorption spectroscopy up to 87.5 GHz. Temperature- and magnetic-field-dependent…

Phonon-phonon anharmonic effects have a strong influence on the phonon spectrum; most prominent manifestation of these effects are the softening (shift in frequency) and broadening (change in FWHM) of the phonon modes at finite temperature.…

Spin and lattice dynamics of CaMn7O12 ceramics were investigated using infrared, THz and inelastic neutron scattering (INS) spectroscopies in the temperature range 2 to 590 K, and, at low temperatures, in applied magnetic fields of up to 12…

We report inelastic light scattering measurements of lattice dynamics related to the incommensurate orbital order in $\mathrm{CaMn_7O_{12}}$. Below the ordering temperature $T_\mathrm{o} \approx 250 \,\mathrm{K}$, we observe extra phonon…

In condensed matter physics broken symmetries and emergence of quasi-particles are intimately linked to each other. Whenever a symmetry is broken, it leaves its fingerprints, and that may be observed indirectly via its influence on the…

The linear spin-wave theory study of PbFeBO4 spin dynamics is presented. It is shown that the modes observed in Raman scattering experiments below Neel temperature are optical magnon and two-magnon excitations. Based on the magnon energy,…

We reported two-magnon Raman scattering from La_{1.9}Sr_{0.1}CuO_4, which has a suppressed Tc=12 K, as the temperature is lowered below 37 K and an ordered spin phase is formed. The two-magnon Raman intensity increases with decreasing…

Hyper-Raman scattering has been measured on vitreous boron oxide, $v-$B$_2$O$_3$. This spectroscopy, complemented with Raman scattering and infrared absorption, reveals the full set of vibrations that can be observed with light. A mode…

We argue that Raman scattering in $B_{1g}$ symmetry allows one to distinguish between phonon-mediated and magnetically-mediated $d-$wave superconductivity. In spin mediated superconductors, $B_{1g}$ Raman intensity develops a resonance at a…

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…

The polarized Raman scattering spectra of nonsuperconducting $\alpha$-FeTe and of the newly discovered, As-free superconductor Fe$_{1.03}$Se$_{0.3}$Te$_{0.7}$ are measured at room temperature on single crystals. The phonon modes are…

Raman spectroscopy is a widely used experimental technique to study the vibrational properties of solids. Atomic scale simulations can be used to predict such spectra, but trustworthy studies at finite temperatures are challenging, mainly…

Ferroelectric soft mode in Pb(Mg1/3Nb2/3)O3 (PMN) has been clearly resolved by precision Raman scattering measurements for the first time. A polarization direction of the incident laser was chosen along [110] in cubic configuration in order…

We report two new first-order Raman modes in the spectra of few-layer MoS$_2$ at 286~cm$^{-1}$ and 471~cm$^{-1}$ for excitation energies above 2.4~eV. These modes appear only in few-layer MoS$_2$; therefore their absence provides an easy…