A false-coloured scanning electron microscopy image of a nominally identical device to the one used in this work. The colours indicate different metallization layers. Six plunger (P i in blue), seven barrier (B i in green) and two screening (yellow) gates form a linear array of six quantum dots (indicated by numbered circles). Two sensing dots (SD i ) are placed at both ends of the array. A cobalt micromagnet, shown in sage grey, is placed on top of the active area, and an in-plane external magnetic field ( B ext ) is applied. Details about the device fabrication and measurement set-up can be found in Supplementary Notes I and XV , respectively.
