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Raman Scattering as a Selective Probe of Chiral Electronic Excitations in Bilayer Graphene

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 نشر من قبل Elisa Riccardi
 تاريخ النشر 2018
  مجال البحث فيزياء
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 تأليف Elisa Riccardi




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We report a symmetry resolved electronic Raman scattering (ERS) study of a bilayer graphene device under gate voltage. We show that the ERS continuum is dominated by interband chiral excitations of $A_{2}$ symmetry and displays a characteristic Pauli-blocking behavior similar to the monolayer case. Crucially, we show that non-chiral excitations make a vanishing contribution to the Raman cross-section due to destructive interference effects in the Raman amplitude matrix elements. This is in a marked contrast to optical absorption measurements and opens interesting venues for the use of Raman scattering as a selective probe of chiral degrees of freedom in topological matter and other 2D crystals.



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