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Thermoelectric transport properties of silicon: Towards an ab initio approach

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 نشر من قبل Zhao Wang
 تاريخ النشر 2018
  مجال البحث فيزياء
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We have combined the Boltzmann transport equation with an {it ab initio} approach to compute the thermoelectric coefficients of semiconductors. Electron-phonon, ionized impurity, and electron-plasmon scattering rates have been taken into account. The electronic band structure and average intervalley deformation potentials for the electron-phonon coupling are obtained from the density functional theory. The linearized Boltzmann equation has then been solved numerically beyond the relaxation time approximation. Our approach has been applied to crystalline silicon. We present results for the mobility, Seebeck coefficient, and electronic contribution to the thermal conductivity, as a function of the carrier concentration and temperature. The calculated coefficients are in good quantitative agreement with experimental results.



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