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We investigated the local potential distribution over gated double-bridge structures patterned on GaAs/GaAlAs heterostructures. The current and potential distribution over the gated double-bridge devices was measured for several sets of filling factors below the two gates and in the ungated region. The fractions of the Hall voltage and the bridge currents experimentally obtained for both bridges correspond exactly to the values predicted by model calculations. Depending on the choice of the filling factor distribution, particular sequences of voltage steps across the bridges can be generated. This might be of some interest for metrological applications. We show that the current and voltage distribution for the double-gate device can be calculated using the edge-current picture. However, it is also shown that exactly the same results can be obtained using a local model in which edge currents are not considered. This has consequences concerning the open question of the extent to which the existence of edge currents in quantizing magnetic fields affects magnetotransport data at integer filling factors.

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