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Trion ground state energy: simple results

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 نشر من قبل Roland Combescot
 تاريخ النشر 2019
  مجال البحث فيزياء
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 تأليف R. Combescot




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We investigate the trion binding energy in a three-dimensional semiconductor, with bare Coulomb interaction between charges, and effective mass approximation for the electron and hole dispersion relations. This is done by making use of a previously proposed exact method for the three-body problem. The calculations cover the complete range of electron-to-hole mass ratio. We find a perfect agreement with existing variational calculations. Investigating the small and large mass ratio regimes, we build a three parameters interpolating formula for the trion binding energy $E_b(r)$ in terms of the exciton binding energy, where $r$ is the electron to exciton mass ratio. This formula $E_b(r)=0.71347-0.11527 ,r -0.18580, sqrt{1-r},$, in atomic units, is in full agreement, within our precision, with our numerical results over the complete range of mass ratio.

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