  Highly uniform quantum systems are essential for the practical implementation
of scalable quantum processors. While quantum dot spin qubits based on
semiconductor technology are a promising platform for large-scale quantum
computing, their small size makes them particularly sensitive to their local
environment. Here, we present a method to electrically obtain a high degree of
uniformity in the intrinsic potential landscape using hysteretic shifts of the
gate voltage characteristics. We demonstrate the tuning of pinch-off voltages
in quantum dot devices over hundreds of millivolts that then remain stable at
least for hours. Applying our method, we homogenize the pinch-off voltages of
the plunger gates in a linear array for four quantum dots reducing the spread
in pinch-off voltage by one order of magnitude. This work provides a new tool
for the tuning of quantum dot devices and offers new perspectives for the
implementation of scalable spin qubit arrays.
