Fig. 3: Numerical modeling of ionic concentrations in a bipolar junction transistor.
From: Ionic amplifying circuits inspired by electronics and biology
a–c Analysis of a device with a 500 nm in diameter pore in 10 mM KCl, pH 8, schematically shown in Fig. 1c. Concentration profiles along the pore axis for a Veb = 3 V, and b Veb = −3 V, and Vec varied as shown in the legend. c Current-voltage curves predicted from the model for Veb = ±3 V. d–f Analysis of a device with 150 nm in diameter pores in 100 mM KCl, pH 8. Scheme of the device is shown in Fig. 1d. Concentration profiles along the pore axis for d Veb = 0.6 V and e Veb = −0.6 V, and Vec varied as shown in the legend. f Current-voltage curves predicted from the model for Veb = ±0.6 V. All concentrations shown are cross-section averaged. A dashed-dotted line in a, b, d, and e indicates bulk concentration of ions. The collector is placed at the position 0 μm. Note that the pores in the two transistors modeled were assumed to be aligned (Supplementary Fig. 5) to assure axial symmetry of the system. g–i Schemes of saturation (g), active (h), and cutoff (i) modes of operation of an ionic transistor.
