TY - JOUR
T1 - Homogeneous nonequilibrium molecular dynamics method for heat transport and spectral decomposition with many-body potentials
AU - Fan, Zheyong
AU - Dong, Haikuan
AU - Harju, Ari
AU - Ala-NissilĂ¤, Tapio
PY - 2019/2/28
Y1 - 2019/2/28
N2 - The standard equilibrium Green-Kubo and nonequilibrium molecular dynamics (MD) methods for computing thermal transport coefficients in solids typically require relatively long simulation times and large system sizes. To this end, we revisit here the homogeneous nonequilibrium MD method by Evans [Phys. Lett. A 91, 457 (1982)PYLAAG0375-960110.1016/0375-9601(82)90748-4] and generalize it to many-body potentials that are required for more realistic materials modeling. We also propose a method for obtaining spectral conductivity and phonon mean-free path from the simulation data. This spectral decomposition method does not require lattice dynamics calculations and can find important applications in spatially complex structures. We benchmark the method by calculating thermal conductivities of three-dimensional silicon, two-dimensional graphene, and a quasi-one-dimensional carbon nanotube and show that the method is about one to two orders of magnitude more efficient than the Green-Kubo method. We apply the spectral decomposition method to examine the long-standing dispute over thermal conductivity convergence vs divergence in carbon nanotubes.
AB - The standard equilibrium Green-Kubo and nonequilibrium molecular dynamics (MD) methods for computing thermal transport coefficients in solids typically require relatively long simulation times and large system sizes. To this end, we revisit here the homogeneous nonequilibrium MD method by Evans [Phys. Lett. A 91, 457 (1982)PYLAAG0375-960110.1016/0375-9601(82)90748-4] and generalize it to many-body potentials that are required for more realistic materials modeling. We also propose a method for obtaining spectral conductivity and phonon mean-free path from the simulation data. This spectral decomposition method does not require lattice dynamics calculations and can find important applications in spatially complex structures. We benchmark the method by calculating thermal conductivities of three-dimensional silicon, two-dimensional graphene, and a quasi-one-dimensional carbon nanotube and show that the method is about one to two orders of magnitude more efficient than the Green-Kubo method. We apply the spectral decomposition method to examine the long-standing dispute over thermal conductivity convergence vs divergence in carbon nanotubes.
KW - THERMAL-CONDUCTIVITY
KW - IRREVERSIBLE-PROCESSES
KW - SIMULATIONS
KW - LIQUID
KW - ORDER
UR - http://www.scopus.com/inward/record.url?scp=85062566400&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.99.064308
DO - 10.1103/PhysRevB.99.064308
M3 - Article
VL - 99
SP - 1
EP - 9
JO - Physical Review B (Condensed Matter and Materials Physics)
JF - Physical Review B (Condensed Matter and Materials Physics)
SN - 2469-9950
IS - 6
M1 - 064308
ER -