Aharonov-Bohm oscillations in bilayer graphene Fabry-Pérot interferometry

Quantum Hall edge state interferometry has been an important tool in probing the charge and statistics of elementary excitations of the quantum Hall and fractional quantum Hall (FQH) effect of a two-dimensional electron gas [1]. Two recent measurements have reported the observations of Aharonov-Bohn oscillations in monolayer graphene quantum Hall interferometers [2,3]. High-quality bilayer graphene is an appealing platform because of the existence of not only odd-denominator FQH states but also candidate non-Abelian even-denominator FQH states with large energy gaps. In this talk, we report on the fabrication and measurements of bilayer graphene Fabry-Pérot interferometer devices and the observation of Aharonov-Bohm oscillations at multiple integer quantum Hall states. We evaluate the edge state interference dephasing under dc bias and at elevated temperatures and discuss the edge mode velocities at different filling factors. We also discuss the progress and challenges towards detecting fractional and non-Abelian statistics in this platform.

[1] Nakamura et al., arXiv:2107.02136

[2] Ronen et al., Nat. Nanotech. 16, 563–569 (2021)

[3] Déprez et al., Nat. Nanotech. 16, 555-562 (2021)