TY  - JOUR
AU  - Yue, Sheng-Ying
AU  - Zhang, Xiaoliang
AU  - Stackhouse, Stephen
AU  - Qin, Guangzhao
AU  - Di Napoli, Edoardo
AU  - Hu, Ming
TI  - Methodology for determining the electronic thermal conductivity of metals via direct nonequilibrium ab initio molecular dynamics
JO  - Physical review / B
VL  - 94
IS  - 7
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2016-04499
SP  - 075149
PY  - 2016
AB  - Many physical properties of metals can be understood in terms of the free electron model, as proven by the Wiedemann-Franz law. According to this model, electronic thermal conductivity can be inferred from the Boltzmann transport equation (BTE). However, the BTE does not perform well for some complex metals, such as Cu. Moreover, the BTE cannot clearly describe the origin of the thermal energy carried by electrons or how this energy is transported in metals. The charge distribution of conduction electrons in metals is known to reflect the electrostatic potential of the ion cores. Based on this premise, we develop a methodology for evaluating electronic thermal conductivity of metals by combining the free electron model and nonequilibrium ab initio molecular dynamics simulations. We confirm that the kinetic energy of thermally excited electrons originates from the energy of the spatial electrostatic potential oscillation, which is induced by the thermal motion of ion cores. This method directly predicts the electronic thermal conductivity of pure metals with a high degree of accuracy, without explicitly addressing any complicated scattering processes of free electrons. Our methodology offers a route to understand the physics of heat transfer by electrons at the atomistic level. The methodology can be further extended to the study of similar electron-involved problems in materials, such as electron-phonon coupling, which is underway currently.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000381889500001
DO  - DOI:10.1103/PhysRevB.94.075149
UR  - https://juser.fz-juelich.de/record/817901
ER  -