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Exciton Mott transition in Si Revealed by Terahertz Spectroscopy

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 نشر من قبل Takeshi Suzuki
 تاريخ النشر 2012
  مجال البحث فيزياء
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Exciton Mott transition in Si is investigated by using terahertz time-domain spectroscopy. The excitonic correlation as manifested by the 1s-2p resonance is observed above the Mott density. The scattering rate of charge carriers is prominently enhanced at the proximity of Mott density, which is attributed to the non-vanishing exciton correlation in the metallic electron-hole plasma. Concomitantly, the signature of plasmon-exciton coupling is observed in the loss function spectra.



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