FIGURE 5.

Dependence of the scaled single channel current on σ_c, channel radius a, and the diffusion coefficients D_c, D_E; solid lines show the approximation Eq. 21 with and dashed and dotted lines show the time-dependent solution of the expressions in Eq. 12. Time is given in units of ((1 + γ)σ_c)⁻¹, which is the relevant timescale for the buildup of the current. Parameter values not mentioned are in Table 1. (a) Scaled single channel current for different σ_c, varied from bottom to top (σ_c, ((1 + γ)σ_c)⁻¹): (10⁷ s⁻¹, 0.05μs), (3 × 10⁶ s⁻¹, 0.17 μs), and (5 × 10⁵ s⁻¹, 1 μs). (b) Scaled single channel current for different channel radii a, varied from bottom to top: 100 nm, 40 nm, and 10 nm. (c) Scaled single channel current for different diffusion coefficients. The dotted lines show the current for D_c = 220 μm² s⁻¹ and D_E from bottom to top: 10 μm² s⁻¹, 40 μm² s⁻¹, and 150 μm² s⁻¹, whereas the dashed lines give the current for D_E = 220 μm² s⁻¹ and D_c from bottom to top: 10 μm² s⁻¹, 40 μm² s⁻¹, and 150 μm² s⁻¹.