FIG. 7.

(a) Density plot of $\sqrt[3]{|\mathrm{U}{|}_{\text{pp}}}$ vs. transit time for 10 μm beads. (b) $\sqrt[3]{|\mathrm{U}{|}_{\text{pp}}}$ versus y-position in channel with color-coded transit time. Inset: schematic of the measurement. There is no observable variation in y-direction. The slower beads causing higher signals in (a) can be explained by beads flowing near the top or bottom of the channel (closer to the electrodes).