We investigated the potential modulation in a novel lateral surface superlattice (LSSL) structure which was realized by utilizing multiatomic steps. The structure was grown by metalorganic vapor-phase epitaxy (MOVPE) on vicinal GaAs substrates to introduce periodic thickness modulation to the channel GaAs layer with spontaneously formed multiatomic steps. Devices having split gates were fabricated on the epitaxially grown LSSL structure. The potential modulation was investigated by a potential sweeping technique, where different bias voltages were applied to the split gates to change the minima of the potential across the multiatomic steps. We observed plateaus and oscillations of conductance as a function of the gate voltage. Systematic shifts of these positions were also observed when offset voltages between the two gates were applied and changed. These features are assumed to originate from the potential modulation induced by multiatomic steps.
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