%0 Book Section %1 statphys23_0573 %A Vitelli, V. %A Xu, N. %A Wyart, M. %A Liu, A.J. %A Nagel, S.R. %B Abstract Book of the XXIII IUPAP International Conference on Statistical Physics %C Genova, Italy %D 2007 %E Pietronero, Luciano %E Loreto, Vittorio %E Zapperi, Stefano %K close diffusivity energy jamming modes packing random soft statphys23 thermal topic-3 transport %T Energy transport in jammed systems %U http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=573 %X We present an analysis of the vibrational modes of jammed packings of soft spheres as a function of compression. A Kubo formula is employed to calculate the frequency-dependent thermal diffusivity using the vibrational normal modes obtained numerically. Structural properties of the modes such as their coordination number and participation ratio are also investigated. We identify the frequency, $ømega_L$, above which the modes are localized and the diffusivity drops rapidly. The majority of the vibrational states occurring at intermediate frequencies, below $ømega_L$, are extended but only minimally conducting. Consistent with earlier results , we find that although there are increasingly more low frequency modes as the density is lowered towards the unjamming transition, the nature of these modes does not change appreciably. However, we do observe a crossover at low frequency (weakly dependent on packing fraction) to resonant modes that are characterized by large displacements at groups of under-coordinated atoms and a low participation ratio.

@incollection{statphys23_0573, abstract = {We present an analysis of the vibrational modes of jammed packings of soft spheres as a function of compression. A Kubo formula is employed to calculate the frequency-dependent thermal diffusivity using the vibrational normal modes obtained numerically. Structural properties of the modes such as their coordination number and participation ratio are also investigated. We identify the frequency, $\omega_L$, above which the modes are localized and the diffusivity drops rapidly. The majority of the vibrational states occurring at intermediate frequencies, below $\omega_L$, are extended but only minimally conducting. Consistent with earlier results , we find that although there are increasingly more low frequency modes as the density is lowered towards the unjamming transition, the nature of these modes does not change appreciably. However, we do observe a crossover at low frequency (weakly dependent on packing fraction) to resonant modes that are characterized by large displacements at groups of under-coordinated atoms and a low participation ratio.}, added-at = {2007-06-20T10:16:09.000+0200}, address = {Genova, Italy}, author = {Vitelli, V. and Xu, N. and Wyart, M. and Liu, A.J. and Nagel, S.R.}, biburl = {https://www.bibsonomy.org/bibtex/25eaac6491d5220691ec2db3496a8acee/statphys23}, booktitle = {Abstract Book of the XXIII IUPAP International Conference on Statistical Physics}, editor = {Pietronero, Luciano and Loreto, Vittorio and Zapperi, Stefano}, interhash = {595db2bfa715d6a97f9e002495d535cf}, intrahash = {5eaac6491d5220691ec2db3496a8acee}, keywords = {close diffusivity energy jamming modes packing random soft statphys23 thermal topic-3 transport}, month = {9-13 July}, timestamp = {2007-06-20T10:16:24.000+0200}, title = {Energy transport in jammed systems}, url = {http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=573}, year = 2007 }