Detection of Fractional Charge in a Quantum Hall Antidot

The detection and control of fractionally charged anyons remain central challenges in condensed matter physics. While recent advances in anyonic interference have revealed phase jumps consistent with fractional statistics, direct measurement of fractional charge is essential for establishing their fundamental properties. Here, we introduce a conceptually simple and tunable platform for quasiparticle manipulation based on a gate-defined antidot in bilayer graphene operated in the Coulomb-dominated regime. This approach enables direct detection of quasiparticle charge through conductance oscillations, bypassing the need for more complex techniques. At filling factors 4/3 and 7/3, we observe oscillations consistent with e/3-charged quasiparticles. Extending these measurements to hole-conjugate states such as 2/3, 5/3, and 8/3, together with new theoretical modeling, reveals distinct tunneling charges arising from integer edge modes. The simplicity and versatility of this platform establish a broadly applicable route to probing fractional charge in van der Waals materials.