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arXiv · 1805.12425

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

Elisa Riccardi·Oleksiy Kashuba·Maximilien Cazayous·Marie-Aude Méasson·Alain Sacuto·Yann Gallais
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Abstract

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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Elisa Riccardi, Oleksiy Kashuba, Maximilien Cazayous, Marie-Aude Méasson, Alain Sacuto, Yann Gallais. 2018-05-31. Raman Scattering as a Selective Probe of Chiral Electronic Excitations in Bilayer Graphene. https://doi.org/10.1103/physrevmaterials.3.014002

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