2022/02/10 by Andrey Pereverzev, Pereverzev, Andrey
Materials Science · #Chemical and Physical Properties of Materials #FOS: Physical sciences #Graphene research and applications #Statistical Mechanics (cond-mat.stat-mech) #Thermal properties of materials
paper · pdf · doi:10.48550/arxiv.2202.05196
openalex publication_date 2022/02/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We re-derive the expression for the heat current for a classical system subject to periodic boundary conditions and show that it can be written as a sum of two terms. The first term is a time derivative of the first moment of the system energy density while the second term is expressed through the energy transfer rate through the periodic boundary. We show that in solids the second term alone leads to the same thermal conductivity as the full expression for the heat current when used in the Green-Kubo approach. More generally, energy passing though any surface formed by translation of the original periodic boundary can be used to calculate thermal conductivity. These statements are verified for two systems: crystalline argon and crystals of argon and krypton forming an interface.