Slow quasiparticle dynamics in graphene-based fractional quantum Hall Fabry-Pérot interferometers

Electronic Fabry-Pérot interferometers (FPIs) in the quantum Hall regime have been investigated for their sensitivity to the exchange statistics of the quasiparticles, which, for anyons, should lead to quantized jumps in the interference phase. Unfortunately, this can be mimicked by Coulomb effects, in which the entry of charged quasiparticles changes the interferometer area. Previous efforts to understand this bulk-edge coupling focus on the energetics of the enclosed quasiparticles. We emphasize a heretofore unappreciated aspect of the experiment concerning the dynamics of these charged quasiparticles. In the integer case, we characterize the time dependence of the quasiparticle content by tracking small phase shifts induced by the bulk-edge coupling. The timescale over which quasiparticles rearrange depends strongly on the magnetic field and electron density, leading to hysteretic charging over timescales ranging from sub-millisecond to several minutes. In the fractional case, we observe a similar timescale, however, the observed phase slips are dominated by the anyonic exchange statistics. The metastable nature allows us to compare the interferometric fingerprint of distinct charge configurations as a function of time, resolving the entry and exit of individual anyons.