Abstract :
We numerically calculate the conductance of a system consisting of an antidot resonator and a point contact, which are isolated from each other by a potential barrier. This system was employed by Kataoka et al. [Phys. Rev. Lett. 83 (1999) 160] to detect the charging around an antidot in the quantum Hall regime. Within a noninteracting model, the point contact conductance is found to develop an Aharonov–Bohm interference oscillation when the tunneling through the barrier is not negligible. Our simulation demonstrates that in order to confirm the charging unambiguously the absence of tunneling must be carefully proven.