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arXiv · 1611.06410

Spatially-indirect Exciton Condensate Phases in Double Bilayer Graphene

Jung-Jung Su·Allan H. MacDonald
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Abstract

We present a theory of spatially indirect exciton condensate states in systems composed of a pair of electrically isolated Bernal graphene bilayers. The ground state phase diagram in a two-dimensional displacement-field/inter-bilayer-bias space includes layer-polarized semiconductors, spin-density-wave states, exciton condensates, and states with mixed excitonic and spin order. We find that two different condensate states, distinguished by a chirality index, are stable under different electrical control conditions.

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Jung-Jung Su, Allan H. MacDonald. 2016-11-19. Spatially-indirect Exciton Condensate Phases in Double Bilayer Graphene. https://doi.org/10.1103/physrevb.95.045416

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