Descreening of Field Effect in Electrically Gated Nanopores

TL;DR

This paper models the electrical behavior of gated nanopores, revealing a descreening effect that causes extended field-effect modulation even in large pores, due to incomplete ionic screening.

Contribution

It introduces a model explaining the descreening phenomenon in nanopores, expanding understanding of ionic transport and gating effects in nanofluidic systems.

Findings

Nonlinear current modulations observed in large nanopores

Descreening effect extends field-effect gating beyond Debye length

Ionic transport prevents full screening of gating potential

Abstract

This modeling work investigates the electrical modulation characteristics of field-effect gated nanopores. Highly nonlinear current modulations are observed in nanopores with non-overlapping electric double layers, including those with pore diameters 100 times the Debye screening length. We attribute this extended field-effect gating to a descreening effect, i.e. the counter-ions do not fully relax to screen the gating potential due to the presence of strong ionic transport.