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arXiv · 2105.07104

Quantum Lifetime Spectroscopy and Magnetotunneling in Double Bilayer Graphene Heterostructures

Nitin Prasad·G. William Burg·Kenji Watanabe·Takashi Taniguchi·Leonard F. Register·Emanuel Tutuc
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Abstract

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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Nitin Prasad, G. William Burg, Kenji Watanabe, Takashi Taniguchi, Leonard F. Register, Emanuel Tutuc. 2021-08-04. Quantum Lifetime Spectroscopy and Magnetotunneling in Double Bilayer Graphene Heterostructures. https://doi.org/10.1103/physrevlett.127.117701

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