A many-body overview of low-energy optical excitations in armchair graphene nanoribbons

Jessica Alfonsi

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arXiv · 1207.3268

A many-body overview of low-energy optical excitations in armchair graphene nanoribbons

Jessica Alfonsi

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Abstract

Excitonic spectra of armchair graphene nanoribbons (AGNRs) obtained from a full many-body exact diagonalization of the Hubbard model are reported for both longitudinally and transversely polarized photons, thus providing a complete survey of low-energy may-body optical excitations in these systems. The resulting one-photon allowed eigenstates turn out to be well separated in energy from each other but both couple to the same set of two-photon allowed states. The magnitude of the calculated optical oscillator strengths for perpendicular polarization suggest that these optical features can be indeed observed in polarized absorption measurements.

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Jessica Alfonsi. 2012-07-13. A many-body overview of low-energy optical excitations in armchair graphene nanoribbons. https://arxiv.org/abs/1207.3268

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