Fig. 5: Valley splitting measurements.
a Typical magnetospectroscopy map of the (1e) → (2e) charge transition, used to measure singlet–triplet splittings. The thin purple line shows the location of the charge transition at a fixed magnetic field. The thick black line is a fit to the data (“Methods”), from which we extract the kink position BST. The valley splitting EV is given by EV = gμBBST, where g = 2 is the gyromagnetic ratio, and μB is the Bohr magneton. b Experimental scatter plots of valley splitting obtained by magnetospectroscopy on complete spin qubit devices. Data from heterostructures with a 6.9(5) nm quantum well (purple, 9 quantum dots from 2 devices) is compared to data from a 9.0(5) nm quantum well (blue, 16 quantum dots, 3 devices, from ref. 5). Dashed lines and shaded area denote the mean value and two standard deviations.
