The problem of phonon scattering by strain fields caused by Stone-Wales (SW) defects in graphene is studied in the framework of the deformation potential approach. An explicit form of the phonon mean free path due to phonon-SW scattering is obtained within the Born approximation. The mean free path demonstrates a specific q-dependence varying as q (-3) at low wavevectors and taking a constant v...

The intriguing coexistence of the charge density wave (CDW) and superconductivity in SrPt2As2 and LaPt2Si2 has been investigated based on the ab initio density functional theory band structure and phonon calculations. We have found that the CDW instabilities for both cases arise from the q-dependent electron-phonon coupling with quasi-nesting feature of the Fermi surface. The band structure obt...

A fundamental understanding of the phonon transport property is crucial to predict the thermal management performance in micro/nano-electronic devices. By combining first principle calculations and Boltzmann phonon transport equation, we investigate thermal transport in TaAs-a typical Weyl semimetal. The lattice thermal conductivity of TaAs at room temperature was found to be 39.26 W mK(-1) and...

Evidence for strong electron-phonon coupling in high-Tc cuprates is reviewed, with emphasis on the electron and phonon spectral functions. Effects due to the interplay between the Coulomb and electron-phonon interactions are studied. For weakly doped cuprates, the phonon self-energy is strongly reduced due to correlation effects, while there is no corresponding strong reduction for the electron...

Raman studies are reported for the A1 TO , E1 TO , E2 , and A1 LO symmetry phonons of AlN from 20 to 375 K. By applying anharmonic decay theory to the observed temperature dependences of the phonon energies and linewidths, we determine the phonon decay mechanisms of these zone-center vibrations. Thermal expansion is taken into account using published temperature-dependent coefficients. The A1 T...

Two-photon excitation experiments were performed to improve understanding of electron–lattice coupling and its effects on intra-3d3 transitions. Cr3+ occupies a scandium octahedral site in K2NaScF6. The transitions studied were A2g → T2g and A2g → T1ag . Complete spectra were recorded at a temperature of 10 K with the polarization vector η̂ parallel to the 〈100〉 or 〈110〉 crystallographic directi...

The elastic modulus of carbyne, a one-dimensional carbon chain, was recently predicted to be much higher than graphene. Inspired by this discovery and the fundamental correlation between elastic modulus and thermal conductivity, we investigate the intrinsic thermal transport in two carbon allotropes: carbyne and cumulene. Using molecular dynamics simulations, we discover that thermal conductivi...