Figure 8.

Temperature−dependence of $\alpha$ for MO10 (yellow circle), derived from the power-law fitting of the V-I curves plotted in the Figure 7. A jump in the value of $\alpha$ from ≃1 to ≃3 (white region) was detected at $T_{BKT}$, corresponding to $T/T_c=0.989$. For comparison, the $\alpha$ values for a 3 nm thick NbN film from the work of Venditti et al. (purple hexagon) [16] and for Mo$S_2$ from the work of Saito et al. (red triangle) [50] were added to the data. The broken line is a guide for the eyes. The temperature was normalized to $T_{BKT}$ for our and Saito et al. data. Venditti et al.’s $\alpha$ values were derived by digitization of Figure (2e) in ref. [16].