Effect of nitrogen and vacancy defects on the thermal conductivity of diamond: An<i>ab initio</i>Green's function approach

“…Recent work by Katcho et al 43 used an ab initio Green's function approach to calculate the effect of nitrogen defects on the thermal conductivity of diamond. They found that nitrogen defects strongly scatter a broader range of phonons than previously thought, from high frequencies to as low as 5 THz.…”

Section: Discussionmentioning

confidence: 99%

Thermal conductance of metal–diamond interfaces at high pressure

2015

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The thermal conductance of interfaces between metals and diamond, which has a comparatively high Debye temperature, is often greater than can be accounted for by twophonon processes. The high pressures achievable in a diamond anvil cell (DAC) can significantly extend the metal phonon density of states to higher frequencies, and can also suppress extrinsic effects by greatly stiffening interface bonding. Here we report time-domain thermoreflectance measurements of metal-diamond interface thermal conductance up to 50 GPa in the DAC for Pb, Au 0.95 Pd 0.05 , Pt and Al films deposited on type 1A natural [100] and type 2A synthetic [110] diamond anvils. In all cases, the thermal conductances increase weakly or saturate to similar values at high pressure. Our results suggest that anharmonic conductance at metal-diamond interfaces is controlled by partial transmission processes, where a diamond phonon that inelastically scatters at the interface absorbs or emits a metal phonon.

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“…Likewise, the expression for 1/τ def jq comes from an atomistic description of each defect, following the ab-initio Green's function approach, as explained in detail in Refs. [23][24][25]. Using the Lippmann-Schwinger equation, 1/τ def jq is given as,…”

Section: Introductionmentioning

confidence: 99%

Unraveling the dominant phonon scattering mechanism in the thermoelectric compound ZrNiSn

2016

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Determining defect types and concentrations remains a big challenge of semiconductor materials science. By using ab-initio thermal conductivity calculations we reveal that Ni/vacancy antisites, and not the previously claimed Sn/Zr antisites, are the dominant defects affecting thermal transport in half-Heusler compound ZrNiSn. Our calculations correctly predict the thermal conductivity dependence with temperature and concentration, in quantitative agreement with published experimental results. Furthermore, we find a characteristic proportionality between phonon-antisite scattering rates and the sixth power of phonon frequency, for which we provide an analytic derivation. These results suggest that thermal conductivity measurements in combination with ab-initio calculations can be used to quantitatively assess defect types and concentrations in semiconductors.

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Effect of nitrogen and vacancy defects on the thermal conductivity of diamond: Anab initioGreen's function approach

Cited by 99 publications

References 39 publications

Defect and Dopant Mediated Thermoelectric Power Factor Tuning in β‐Zn₄Sb₃

Defect and Dopant Mediated Thermoelectric Power Factor Tuning in β‐Zn₄Sb₃

Thermal conductance of metal–diamond interfaces at high pressure

Unraveling the dominant phonon scattering mechanism in the thermoelectric compound ZrNiSn

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Effect of nitrogen and vacancy defects on the thermal conductivity of diamond: Anab initioGreen's function approach

Cited by 99 publications

References 39 publications

Defect and Dopant Mediated Thermoelectric Power Factor Tuning in β‐Zn4Sb3

Defect and Dopant Mediated Thermoelectric Power Factor Tuning in β‐Zn4Sb3

Thermal conductance of metal–diamond interfaces at high pressure

Unraveling the dominant phonon scattering mechanism in the thermoelectric compound ZrNiSn

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Product

Resources

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Defect and Dopant Mediated Thermoelectric Power Factor Tuning in β‐Zn₄Sb₃

Defect and Dopant Mediated Thermoelectric Power Factor Tuning in β‐Zn₄Sb₃