We introduce a versatile two-step electron-beam fabrication technique for defining multiport quantum dots in GaAs/AlGaAs heterostructures in close vicinity. Capacitive coupling of the two quantum dots is directly tuned electrostatically via two central gates. Parallel access is realized by patterning source and drain contact regions of both dots with an additional spacer layer. Conductance measurements give evidence of both the continuous wide-range tunability of the dots and parallel access to the circuit.

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