Fig. 4: Exchange of two electrons by permutation within a 2D array.
From: Single-electron operations in a foundry-fabricated array of quantum dots
a Ground-state region of the 111 triple dot from Fig. 2d (\({V}_{{{2}}}^{\mathrm{c}}=\)constant), plotted in three-dimensional control-voltage space, along measurements within a plane of fixed common-mode voltage (\({\epsilon }_{{{1}}}^{\mathrm{c}}=\)constant). Physically, \({\epsilon }_{{{1}}}^{\mathrm{c}}\) induces overall gate charge in the array, whereas detuning \({\epsilon }_{{{2}}}^{\mathrm{c}}\) (\({\epsilon }_{{{3}}}^{\mathrm{c}}\)) relocates gate charge within the array along (across) the silicon channel. b Guides to the eye indicating different ground states within the detuning plane in a. For this choice of sensor operating point, \({{V}_{4}^{\mathrm{o}}}=595\,\) mV, VH does not discriminate between different two-electron configurations. c Same detuning plane as in b, but with slightly different sensor operating point, \({{V}_{4}^{\mathrm{o}}}=592\,\) mV. The control-voltage path C traverses three two-electron ground states in such a way that the two isolated electrons are exchanged within the array. d Sensor signal VH acquired during one cycle of the shuttling path C. Changes in VH reflect single-electron movements within the array, as illustrated by red arrows. After completion of one cycle C, the position of the two electrons in the array has been permuted.
