Tuning ion current rectification in asymmetric nanopores by signal mixingE. Kalman1, K. Healy2 and Z. S. Siwy1
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
received 28 November 2006; accepted in final form 26 February 2007; published April 2007
published online 27 March 2007
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.
81.07.De - Nanotubes.
81.16.-c - Methods of nanofabrication and processing.
87.16.Uv - Active transport processes; ion channels.
© Europhysics Letters Association 2007