Tuning ion current rectification in asymmetric nanopores by signal mixing

¹  Department of Physics and Astronomy, University of California, Irvine - Irvine, CA 92697, USA
²  Department of Electrical and Electronic Engineering, University College Cork - Cork, Ireland

Corresponding author: zsiwy@uci.edu

Received: 28 November 2006
Accepted: 26 February 2007

Abstract

Transport properties of asymmetric and rectifying single nanopores in polymer films were studied in the presence of a sum of two periodic, rectangular voltage signals, with the aim of testing signal mixing as a tool for tuning ion current rectification. Current-voltage curves and net ion currents were recorded when the two voltage signals were added with a controlled phase difference. We show that changing the ratio of frequencies, the phase difference and amplitude of the two voltage inputs gives a new possibility to enhance, hinder or cancel the rectifying properties of the nanoporous system. Our experimental results are explained by a model of a doubly rocked ratchet in the adiabatic regime, presented in Europhys. Lett., 67 (2004) 179.