A tunable Fabry-Pérot quantum Hall interferometer in graphene

Electron interferometry with quantum Hall edge channels in semiconductor heterostructures can probe and harness the exchange statistics of anyonic excitations. However, charging effects present in semiconductors often obscured the Aharonov-Bohm interference in quantum Hall interferometers and make advanced charge screening strategies necessary. Here, we show that high-mobility monolayer graphene constitutes an alternative material system, not affected by charging effects, to perform Fabry-Pérot quantum Hall interferometry in the integer quantum Hall regime. In devices equipped with gate-tunable quantum point contacts acting on the edge channels of the zeroth Landau level, we observe high-visibility Aharonov-Bohm interference widely tunable through electrostatic gating or magnetic field, in agreement with theory. A coherence length of 10 μm at a temperature of 0.02 K allows us to further achieve coherently-coupled double Fabry-Pérot interferometry. In future, quantum Hall interferometry with graphene devices may enable investigations of anyonic excitations in fractional quantum Hall states.