Thermal conductance of structured silicon nanocrystals
Abstract
We calculate the thermal conductance of a structured silicon nanocrystal with a hole of different sizes. The numerical study is based on non-equilibrium molecular dynamics simulations using two potential models for the interatomic interactions: (i) an empirical Tersoff-Brenner (Tersoff) potential; (ii) a semi-empirical tight binding (TB) potential. TB potential model predicts a similar thermal conductance for the nanocrystal with no hole and with a small size hole, which contrasts with the monotonic decrease predicted by Tersoff potential model. In addition, thermal conductance decreasing is higher for TB potential model when the surface-to-volume ratio increases. This points out that to study thermal properties of nanostructures with high surface-to-volume ratio is mandatory the use of potential models with high transferability to take adequately into account the relevant quantum physical effects due to boundaries and surfaces.
- Publication:
-
Modelling Simul. Mater. Sci. Eng.
- Pub Date:
- October 2020
- DOI:
- 10.1088/1361-651X/aba8eb
- Bibcode:
- 2020MSMSE..28g5004B
- Keywords:
-
- silicon;
- heat transport;
- thermal conductivity;
- tight binding potential;
- Tersoff potential;
- molecular dynamics;
- nanocrystal