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Thermal conductivity and thermal boundary resistance of nanostructures.

Termentzidis K, Parasuraman J, Da Cruz CA, Merabia S, Angelescu D, Marty F, Bourouina T, Kleber X, Chantrenne P, Basset P - Nanoscale Res Lett (2011)

Bottom Line: The influence of the interfacial roughness on the thermal conductivity of semiconductor/semiconductor superlattices was studied by equilibrium and non-equilibrium molecular dynamics and on the Kapitza resistance of superlattice's interfaces by equilibrium molecular dynamics.Physical explanations are provided for rationalizing the simulation results.PACS: 68.65.Cd, 66.70.Df, 81.16.-c, 65.80.-g, 31.12.xv.

View Article: PubMed Central - HTML - PubMed

Affiliation: INSA Lyon, CETHIL UMR5008, F-69621 Villeurbanne, France. konstantinos.termentzidis@gmail.com.

ABSTRACT
: We present a fabrication process of low-cost superlattices and simulations related with the heat dissipation on them. The influence of the interfacial roughness on the thermal conductivity of semiconductor/semiconductor superlattices was studied by equilibrium and non-equilibrium molecular dynamics and on the Kapitza resistance of superlattice's interfaces by equilibrium molecular dynamics. The non-equilibrium method was the tool used for the prediction of the Kapitza resistance for a binary semiconductor/metal system. Physical explanations are provided for rationalizing the simulation results. PACS: 68.65.Cd, 66.70.Df, 81.16.-c, 65.80.-g, 31.12.xv.

No MeSH data available.


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Kapitza resistance function of the height of superlattice's interfaces.
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Figure 5: Kapitza resistance function of the height of superlattice's interfaces.

Mentions: Figure 5 displays the generalised Kapitza resistances measured with MD for superlattices with rough interfaces having variable roughnesses. Again, the results are displayed in LJU, which correspond to a resistance of 10 × 10-9 m2K/W in SI units. The period of the superlattice considered is larger than the PMFP, which here is estimated to be around 20a0. We have focused on two peculiar orientations θ = 0 and θ = π/2 which correspond, respectively, to the cross-plane and in-plane directions of the superlattices. It is striking that, for a given interfacial roughness, the computed resistance depends on the orientation θ. We have found that for almost all the systems analysed, the Kapitza resistance is larger in the cross-plane direction than in the direction parallel to the interfaces. This is consistent with the observation that the thermal conductivity is the largest in the in-plane direction (Figure 4). Again, this reinforces the message that the heat transfer properties of superlattices are explained by the phononic nature of the energy carriers, and that theses energy carriers feel less friction in the in-plane direction than that in the direction normal to the interfaces. Measuring the directional Kapitza resistance is a first step towards a quantitative measurement of the transmission factor of phonons depending on their direction of propagation across an interface.


Thermal conductivity and thermal boundary resistance of nanostructures.

Termentzidis K, Parasuraman J, Da Cruz CA, Merabia S, Angelescu D, Marty F, Bourouina T, Kleber X, Chantrenne P, Basset P - Nanoscale Res Lett (2011)

Kapitza resistance function of the height of superlattice's interfaces.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211353&req=5

Figure 5: Kapitza resistance function of the height of superlattice's interfaces.
Mentions: Figure 5 displays the generalised Kapitza resistances measured with MD for superlattices with rough interfaces having variable roughnesses. Again, the results are displayed in LJU, which correspond to a resistance of 10 × 10-9 m2K/W in SI units. The period of the superlattice considered is larger than the PMFP, which here is estimated to be around 20a0. We have focused on two peculiar orientations θ = 0 and θ = π/2 which correspond, respectively, to the cross-plane and in-plane directions of the superlattices. It is striking that, for a given interfacial roughness, the computed resistance depends on the orientation θ. We have found that for almost all the systems analysed, the Kapitza resistance is larger in the cross-plane direction than in the direction parallel to the interfaces. This is consistent with the observation that the thermal conductivity is the largest in the in-plane direction (Figure 4). Again, this reinforces the message that the heat transfer properties of superlattices are explained by the phononic nature of the energy carriers, and that theses energy carriers feel less friction in the in-plane direction than that in the direction normal to the interfaces. Measuring the directional Kapitza resistance is a first step towards a quantitative measurement of the transmission factor of phonons depending on their direction of propagation across an interface.

Bottom Line: The influence of the interfacial roughness on the thermal conductivity of semiconductor/semiconductor superlattices was studied by equilibrium and non-equilibrium molecular dynamics and on the Kapitza resistance of superlattice's interfaces by equilibrium molecular dynamics.Physical explanations are provided for rationalizing the simulation results.PACS: 68.65.Cd, 66.70.Df, 81.16.-c, 65.80.-g, 31.12.xv.

View Article: PubMed Central - HTML - PubMed

Affiliation: INSA Lyon, CETHIL UMR5008, F-69621 Villeurbanne, France. konstantinos.termentzidis@gmail.com.

ABSTRACT
: We present a fabrication process of low-cost superlattices and simulations related with the heat dissipation on them. The influence of the interfacial roughness on the thermal conductivity of semiconductor/semiconductor superlattices was studied by equilibrium and non-equilibrium molecular dynamics and on the Kapitza resistance of superlattice's interfaces by equilibrium molecular dynamics. The non-equilibrium method was the tool used for the prediction of the Kapitza resistance for a binary semiconductor/metal system. Physical explanations are provided for rationalizing the simulation results. PACS: 68.65.Cd, 66.70.Df, 81.16.-c, 65.80.-g, 31.12.xv.

No MeSH data available.


Related in: MedlinePlus