Related papers: Phonon anharmonicity and soft-phonon mediated stru…
We report a comparative Raman spectroscopic study of the quasi-one-dimensional charge-density-wave systems \ab (A = K, Rb). The temperature and polarization dependent experiments reveal charge-coupled vibrational Raman features. The…
The interplay between different degrees of freedom such as charge, spin, orbital, and lattice has received a great deal of interest due to its potential to engineer materials properties and their functionalities for device applications. In…
The recently discovered layered BiS2-based superconductors have attracted a great deal of interest due to their structural similarity to cuprate and iron-pnictide superconductors. We have performed Raman scattering measurements on two…
Despite the widespread use of silicon in modern technology, its peculiar thermal expansion is not well-understood. Adapting harmonic phonons to the specific volume at temperature, the quasiharmonic approximation, has become accepted for…
We investigate the influence of three- and four-phonon scattering, perturbative anharmonic phonon renormalization, and off-diagonal terms of coherent phonons on the thermal conductivity of CsPbBr3 phase change perovskite, by using advanced…
We report inelastic light scattering studies on Ca(Fe0.97Co0.03)2As2 in a wide spectral range of 120-5200 cm-1 from 5K to 300K, covering the tetragonal to orthorhombic structural transition as well as magnetic transition at Tsm ~ 160K. The…
Phonon-derived behaviors are important indicators of novel phenomena in transition metal trihalides, including spin liquid behavior, two-dimensional magnetism, and spin-lattice coupling. However, phonons and their dependence on spin…
It is well known that conventional harmonic lattice dynamics cannot be applied to energetically unstable crystals at 0 K, such as high temperature body centered cubic (BCC) phase of crystalline Zr. Predicting phonon spectra at finite…
The Raman active G mode in graphene exhibits strong coupling to electrons, yet the comprehensive treatment of this interaction in the calculation of its temperature-dependent Raman spectrum remains incomplete. In this study, we calculate…
We investigated the crystal structure and lattice excitations of the ternary intermetallic stannide Ca3Ir4Sn13 using neutron and x-ray scattering techniques. For T > T* ~ 38 K the x-ray diffraction data can be satisfactorily refined using…
For many materials, Raman spectra are intricately structured and provide valuable information about compositional stoichiometry and crystal quality. Here we use density-functional theory calculations, mass approximation, and the Raman…
Temperature dependence of longitudinal optical phonons with oxygen character was measured in La1-xSrxMnO3 (x=0.2, 0.3) by inelastic neutron scattering in the (1 0 0) cubic direction. The zone center mode intensity is consistent with the…
Bismuth selenide, a benchmark topological insulator, grows in a trigonal structure at ambient conditions and exhibits a number of enticing properties related to the formation of Dirac surface states. Besides this polytype, a metastable…
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…
An experimental study of optical phonon modes, both normal and interface (IF) phonons, in bilayer strain-coupled InAs/GaAs_(1-x)Sb_x quantum dot heterostructures has been presented by means of low-temperature polarized Raman scattering. The…
We report inelastic light scattering experiments on CaFe_2As_2 in the temperature range of 4 to 290 K. In in-plane polarizations two Raman-active phonon modes are observed at 189 and 211 cm-1, displaying A_1g and B_1g symmetries,…
Parent compounds of Fe-based superconductors undergo a structural phase transition from a tetragonal to an orthorhombic structure. We investigated the temperature dependence of the frequencies of transverse acoustic (TA) phonons that…
The temperature dependence of the phonon spectrum in the superconducting transition metal dichalcogenide 2H-NbS$_2$ is measured by diffuse and inelastic x-ray scattering. A deep, wide and strongly temperature dependent softening, of the two…
We investigate phonon lifetimes in VO2 single crystals. We do so in the metallic state above the metal-insulator transition (MIT), where strong structural fluctuations are known to take place. By combining inelastic X-ray scattering and…
Magnetic and crystallographic transitions in the Cairo pentagonal magnet Bi2Fe4O9 are investigated by means of infrared synchrotron-based spectroscopy as a function of temperature (20 - 300 K) and pressure (0 - 15.5 GPa). One of the phonon…