Fig. 2: Conductance switching.
From: Quasiparticle tunnel electroresistance in superconducting junctions
Differential conductance G = dI/dVBIAS as a function of applied VBIAS, measured at T = 3.2 K after application of Vpol > 0 V (ON state) and Vpol < 0 V (OFF state) for three different BFO thickness. a 0 nm BFO-Mn (Vpol = ± 3 V), c 3nmBFO-Mn (Vpol = + 6 V and −4V) and e 15nmBFO-Mn (Vpol = ± 4 V). For the latter thickness, the conductance in the OFF state is unmeasurably low. d, e, f show the switching between the ON and OFF state. This is illustrated by G0(Vpol)and G100(Vpol), that is, the conductance measured at zero bias and at VBIAS = 100 mV after application of different Vpol, which were cycled repeatedly from negative to positive and vice versa. For the same samples as in a–c. g–i show Go(T) and G100(T) after poling at 3.2 K. The straight lines superposed to the measurements in the OFF state are a extrapolation of the high temperature trend of G(T). Green regions highlight the deviation of Go(T) from the high temperature trend. The inset in (i) shows the ratio between the electroresistance (ER = GON/GOFF) at zero bias and that under VBIAS = 100 mV, that is ER0/ER100, as a function of temperature for the 0 nm BFO (diamonds), and 3 nm BFO junction (squares symbols). ER0/ER100 is calculated from the data in 2 g and 2 h. The green region highlights the deviation of ER0/ER100 from the high temperature trend. The vertical axis presents a break between ER0/ER100 = 10 and ER0/ER100 = 25.
