Hi,
Thank you for Nice GPUMD program and I have question today.
When we deal with thermal conductivity of graphene at temperature below the
debye temperature,
it is reported in many papers that the thermal conductivity should be treated
with quantum-correction.
So I saw there are generally two methods that
1. from the paper1: Equilibrium Molecular Dynamics (MD) Simulation Study of
Thermal Conductivity of Graphene Nanoribbon: A Comparative Study on MD
Potentials (Electronics 2015, 4, 1109-1124)
which said that it can be calculated with thermal conductivity of MD (k_md)
multiplied by d(Tmd)/d(Tq), following the equation13 in the paper.
and
2. from the paper2: Lateral and flexural thermal transport in stanene/2D-SiC
van der Waals heterostructure, (2020 Nanotechnology 2020 31 505702)
which said that it can be calculated from Cv (specific heat) which can be
obtained with integration of phonon density of states.
As I got the phonon DOS at 300K and followed second method, Cvx=Cvy=0.18 and
Cvz=0.5
and I obtained quantum-corrected thermal conducivity of
k_in-plane=1000*Cvy=180, k_flexural= 2000*Cvz=1000 (W/mK)
so that ktot=k_in-plane+k_flexural=1180 (W/mK)
However, this value is much lower than that in paper1, which shows little
difference after quantum-correction at 300K.
How can this problem be solved?
