Theoretical study of NMR relaxation due to rattling phonons
arXiv:0710.5668 · doi:10.1016/j.jpcs.2008.06.048
Abstract
We calculate the NMR relaxation rate due to quadrupolar coupling of the nucleus to a local, strongly anharmonic phonon mode. As a model potential for a rattling motion we consider a square-well potential. We calculate the free phonon Green's function analytically and derive the low and high temperature limits of the NMR relaxation rate. It is shown that the temperature dependence of the NMR relaxation rate possesses a peak in contrast to harmonic phonons but in qualitative agreement with a recent NMR study on KOs2O6. We discuss the influence of phonon renormalization due to electron-phonon interaction.
5 pages, 3 figures, SNS2007 (Sendai, Japan) conference proceedings, accepted for publication
References in corpus (4)
- Extremely strong-coupling superconductivity and anomalous lattice properties in the beta-pyrochlore oxide KOs2O6
- NMR relaxation and resistivity from rattling phonons in pyrochlore superconductors
- NMR Observation of Rattling Phonons in the Pyrochlore Superconductor KOs2O6
- Thermal Conductivity of the Pyrochlore Superconductor KOs2O6: Strong Electron Correlations and Fully Gapped Superconductivity