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Quantum Lifetime Spectroscopy and Magnetotunneling in Double Bilayer Graphene Heterostructures

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 نشر من قبل Emanuel Tutuc
 تاريخ النشر 2021
  مجال البحث فيزياء
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We describe a tunneling spectroscopy technique in a double bilayer graphene heterostructure where momentum-conserving tunneling between different energy bands serves as an energy filter for the tunneling carriers, and allows a measurement of the quasi-particle state broadening at well defined energies. The broadening increases linearly with the excited state energy with respect to the Fermi level, and is weakly dependent on temperature. In-plane magnetotunneling reveals a high degree of rotational alignment between the graphene bilayers, and an absence of momentum randomizing processes.



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