We study thermal transport in porous Si nanowires (SiNWs) by means of approach-to-equilibrium molecular dynamics simulations. We show that the presence of pores greatly reduces the thermal conductivity, κ, of the SiNWs as long mean free path phonons are suppressed. We address explicitly the dependence of κ on different features of the pore topology - such as the porosity and the pore diameter - and on the nanowire (NW) geometry - diameter and length. We use the results of the molecular dynamics calculations to tune an effective model, which is capable of capturing the dependence of κ on porosity and NW diameter. The model illustrates the failure of Matthiessen's rule to describe the coupling between boundary and pore scattering, which we account for by the inclusion of an additional empirical term

Thermal transport in porous Si nanowires from approach-to-equilibrium molecular dynamics calculations

DETTORI, RICCARDO;MELIS, CLAUDIO;COLOMBO, LUCIANO;
2016

Abstract

We study thermal transport in porous Si nanowires (SiNWs) by means of approach-to-equilibrium molecular dynamics simulations. We show that the presence of pores greatly reduces the thermal conductivity, κ, of the SiNWs as long mean free path phonons are suppressed. We address explicitly the dependence of κ on different features of the pore topology - such as the porosity and the pore diameter - and on the nanowire (NW) geometry - diameter and length. We use the results of the molecular dynamics calculations to tune an effective model, which is capable of capturing the dependence of κ on porosity and NW diameter. The model illustrates the failure of Matthiessen's rule to describe the coupling between boundary and pore scattering, which we account for by the inclusion of an additional empirical term
SILICON NANOWIRES, CONDUCTIVITY, HEAT, SOLIDS
File in questo prodotto:
File Dimensione Formato  
1.4955038.pdf

embargo fino al 04/07/2017

Tipologia: versione editoriale
Dimensione 2.07 MB
Formato Adobe PDF
2.07 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11584/174525
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 20
  • ???jsp.display-item.citation.isi??? 19
social impact