Measurement of the curvature and height of the potential barrier for a dynamic quantum dot

We note that this solution only gives a linear dependence on V_exit in the subject of the interior exponent, and that some references, including 2 and 22 use an alternative construction of $δn$⁠.

We note there was a discontinuity seen around T = 32 K, arising from a thermal cycle occurring to the device. On remeasuring the device, it was found δ₁ was unchanged (ensuring consistency and generality of results) but the position in V_exit had slightly shifted by 14 mV. This has been accounted for in this analysis by offsetting curves for T < 32 K. Note that the curves of Figs. 1(c), 1(d), 2(a), and 3(a) are also offset.

In the analysis of Fig. 3(b), low temperature data was excluded from the fit owing to instability of the curve position in V_exit, which we speculate is due to a changing channel conductance.⁴⁰ 

The error bars plotted in Fig. 3(b) are the Type A (statistical) uncertainty, and these are used in the fit. The limit of our measurement resolution, and hence Type A uncertainty, is approximately 0.2 pA, which corresponds to $ln (−ln (Ip/ef))∼6$⁠, and points below this are not used in the fit. To show the crossover to the tunneling regime, we extend the fit curve in to this region.