Recovery of normal heat conduction in harmonic chains with correlated disorder
1 Instituto de Física, Universidad Autónoma de Puebla - Apartado Postal J-48, Puebla, Pue., 72570, Mexico
2 Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo Morelia, Mich., 58060, Mexico
Received: 27 March 2015
Accepted: 11 June 2015
We consider heat transport in one-dimensional harmonic chains with isotopic disorder, focusing our attention mainly on how disorder correlations affect heat conduction. Our approach reveals that long-range correlations can change the number of low-frequency extended states. As a result, with a proper choice of correlations one can control how the conductivity κ scales with the chain length N. We present a detailed analysis of the role of specific long-range correlations for which a size-independent conductivity is exactly recovered in the case of fixed boundary conditions. As for free boundary conditions, we show that disorder correlations can lead to a conductivity scaling as , with the scaling exponent ε being arbitrarily small (although not strictly zero), so that normal conduction is almost recovered even in this case.
PACS: 44.10.+i – Heat conduction / 63.50.Gh – Disordered crystalline alloys / 63.22.-m – Phonons or vibrational states in low-dimensional structures and nanoscale materials
© EPLA, 2015