Strongly bound excitons dominate electronic relaxation in resonantly excited twisted bilayer graphene

@inproceedings{Patel2015StronglyBE,
  title={Strongly bound excitons dominate electronic relaxation in resonantly excited twisted bilayer graphene},
  author={Hiral Patel and Lola Brown and Yufeng Liang and Li Yang and Jiwoong Park and Matt W. Graham},
  year={2015}
}
When two sheets of graphene stack in a twisted bilayer graphene (tBLG) configuration, the resulting constrained overlap between interplanar 2p orbitals produce angle-tunable electronic absorption resonances. Using a novel combination of multiphoton transient absorption (TA) microscopy and TEM, we resolve the resonant electronic structure, and ensuing electronic relaxation inside single tBLG domains. Strikingly, we find that the transient electronic population in resonantly excited tBLG domains… 
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