Disorder-induced mobility edges and heat flow control in anharmonic acoustic chains
Theory of Oscillations Department, University of Nizhniy Novgorod - Nizhniy Novgorod, Russia
2 Max-Planck-Institut für Physik komplexer Systeme - Nöthnitzer Str. 38, 01187 Dresden, Germany, EU
Accepted: 11 April 2011
We control the thermal conductivity of anharmonic acoustic chains by varying the strength of disorder in the interaction. It induces mobility edges in the phonon spectrum. Therefore we limit the amount of extended modes which can ballistically propagate. The rest of the modes becomes localized and opens a diffusive heat conductivity channel. The localized modes are sensitively controlling the contact resistances at the edges. Analytical arguments and numerical results yield several crossovers between dominating heat channels, when varying the system size and the temperature.
PACS: 63.20.Pw – Localized modes / 63.20.Ry – Anharmonic lattice modes / 05.45.-a – Nonlinear dynamics and chaos
© EPLA, 2011