Coulomb-Dominated Oscillations in Fabry–Perot Quantum Hall Interferometers

Periodic resistance oscillations in Fabry–Perot quantum Hall interferometers are observed at integer filling factors of the constrictions, f_\rm c=1, 2, 3, 4, 5 and 6. Rather than the Aharonov–Bohm interference, these oscillations are attributed to the Coulomb interactions between interfering edge states and localized states in the central island of an interferometer, as confirmed by the observation of a positive slope for the lines of constant oscillation phase in the image plot of resistance in the B–V_\rm S plane. Similar resistance oscillations are also observed when the area A of the center regime and the backscattering probability of interfering edge states are varied, by changing the side-gate voltages and the configuration of the quantum point contacts, respectively. The oscillation amplitudes decay exponentially with temperature in the range of 40 mK < T\leq 130 mK, with a characteristic temperature T_\rm 0\sim 25 mK, consistent with recent theoretical and experimental works.