Phononic heat conduction in disordered crystals
A. Dhar
Raman Institute,
Abstract: We investigate the question as to
whether disordered harmonic crystals in two and three dimensions have a finite
thermal conductivity. A heuristic argument using localization theory and
kinetic theory is given to estimate the system size dependence of the current.
Numerical results testing these predictions will be discussed. The numerical
studies are based on the Landauer formula using
phonon transmission and also on nonequilibrium
simulations. The role of ballistic and diffusive phonon modes and the effect of
boundary conditions are critically analyzed. The effect of anharmonicity
will also be briefly discussed.