Interplay between chiral edge channels and localized states in a quantum dot

We study electronic transport through a gate-defined quantum-dot (QD) embedded in a high mobility two-dimensional electron gas in GaAs, subjected to a perpendicular magnetic field. In the Quantum Hall Effect regime, chiral edge channels interact with confined electronic states in the dot, allowing a detailed study of edge channels coupled to localized states. Employing low-temperature transport measurements, we map the evolution of Coulomb-Blockade resonances with the magnetic field, the plunger gate voltage, and the source-drain bias. Distinct conductance features reveal the interplay between Landau quantization and the quantization of localized states imposed by the dot’s geometry. This interplay reflects the gradual transition from the transport of the extended edge states to transport dominated by discrete localized states. Our measurements provide new insight into the transition, where the edge channels couple to the confined electron pool in the dot. We demonstrate that quantum dots can serve as sensitive probes of the microscopic structure of edge excitations and localized states.