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arXiv · 2004.10582

Strain induced quantum Hall effect of excitons in graphene

Oleg L. Berman·Roman Ya. Kezerashvili·Yurii E. Lozovik·Klaus G. Ziegler
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Abstract

We study the effect of a uniform pseudomagnetic field, induced by a strain in a monolayer and double layer of gapped graphene, acting on excitons. For our analysis it is crucial that the pseudomagnetic field acts on the charges of the constituent particles of the excitons, i.e., the electrons and holes, the same way in contrast to a magnetic field. Moreover, using a circularly polarized laser field, the electrons and the holes can be excited only in one valley of the honeycomb lattice of gapped graphene. This breaks the time-reversal symmetry and provides the possibility to observe the various Quantum Hall phenomena in this pseudomagnetoexciton system. Our study poses a fundamental problem of the quantum Hall effect for composite particles and paves the way for quantum Hall physics of pseudomagnetoexcitons.

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Oleg L. Berman, Roman Ya. Kezerashvili, Yurii E. Lozovik, Klaus G. Ziegler. 2020-12-05. Strain induced quantum Hall effect of excitons in graphene. https://doi.org/10.1038/s41598-022-06486-z

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