A water-based molecular flip-flop

¹ Department of Physics, Zhejiang Agriculture and Forestry University, Hangzhou, Linan 311300, P.R. China
² Zhejiang Provincial Key Laboratory of Chemical Utilization of Forestry Biomass, Zhejiang Agriculture and Forestry University, Hangzhou, Linan 311300, P.R. China
³ Department of Physics, Fudan University, Shanghai 200433, P.R. China

^a e-mail: yuwang_zafu@126.com
^b e-mail: jphuang@fudan.edu.cn

Received: 5 June 2014
Revised: 28 October 2014
Accepted: 6 November 2014
Published online: 12 December 2014

Abstract

The flip-flop, which has been widely used in digital circuits, has two stable states and can be used to store state information. Because traditional flip-flops based on digital circuits suffer from a barrier to higher performance, it is necessary to explore some new alternative devices. For this purpose, we utilize molecular dynamics simulations to design a molecular flip-flop, which contains one water molecule confined within a single-walled carbon nanotube. Its two states can be switched within 0.5 ps (2000 GHz), and its state information can be exported by the charged atomic-force microscope force probes. The mechanism of the flip-flop depends on the behavior of a water molecule in a nonuniform electric field. In particular, a water molecule always moves toward the location of lowest electric energy in a nonuniform electric field generated by point charges. The resulting flip-flop could be utilized for designing nanoscale devices.