Shukla Abhay, Calandra Matteo, D'Astuto Matteo, Lazzeri Michele, Mauri Francesco, Bellin Christophe, Krisch Michael, Karpinski J, Kazakov S M, Jun J, Daghero D, Parlinski K
Laboratoire de Minéralogie-Cristallographie, case 115, 4 Place Jussieu, 75252, Paris cedex 05, France.
Phys Rev Lett. 2003 Mar 7;90(9):095506. doi: 10.1103/PhysRevLett.90.095506.
We measure phonon dispersion and linewidth in a single crystal of MgB2 along the Gamma-A, Gamma-M, and A-L directions using inelastic x-ray scattering. We use density functional theory to compute the effect of both electron-phonon coupling and anharmonicity on the linewidth, obtaining excellent agreement with experiment. Anomalous broadening of the E(2g) phonon mode is found all along Gamma-A. The dominant contribution to the linewidth is always the electron-phonon coupling.
