Exciton Mott transition in Si Revealed by Terahertz Spectroscopy

Takeshi Suzuki; Ryo Shimano

doi:10.1103/physrevlett.109.046402

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arXiv · 1203.5179

Exciton Mott transition in Si Revealed by Terahertz Spectroscopy

Takeshi Suzuki·Ryo Shimano

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Abstract

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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Takeshi Suzuki, Ryo Shimano. 2012-07-13. Exciton Mott transition in Si Revealed by Terahertz Spectroscopy. https://doi.org/10.1103/physrevlett.109.046402

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