Past Events

Abstract
 

Phonon thermal transport is a stochastic process in nature, and the distribution function of the physics quantities involved is usually non-Gaussian, such as heat current and thermal conductance, the fully characterizations of which require high order cumulants besides mean value and standard deviation. On one hand, the brute force approach, taking average by generating numerous configurations with given random distribution, is widely used. However, this method is numerical prohibitive when dealing with relatively large disordered systems. On the other hand, full counting statistics (FCS) method in electronic transport, based on nonequilibrium Green's function (NEGF) theory, is proved to be more time efficient by directly taking average on the cumulant generating function (CGF). Although electron transport calculation shares lots of similarities with phonon thermal transport, few works have been reported on applying FCS approach to phonon disordered systems.

In this talk, I will briefly go through the FCS approach in electron conductance disordered system, figure out the difficulties when applying FCS to phonon thermal transport calculations, and make a comparison with brute force calculation. In square lattice model and zigzag-graphene lattice model with binary or Anderson isotopic disorder, our numerical results are greatly consistent with corresponding results obtained by brute force method, but much more time efficient.

Anyone interested is welcome to attend.