A charge-driven molecular flip-flop

¹ Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, P.R. China
² Department of Physics, Zhejiang Agriculture and Forestry University, Linan 311300, P.R. China
³ Advanced Materials Laboratory, Fudan University, Shanghai 200438, P.R. China

^a e-mail: yuwang79@gmail.com
^b e-mail: zhaoyanjiao@fudan.edu.cn
^c e-mail: jphuang@fudan.edu.cn

Received: 4 September 2012
Revised: 6 January 2013
Accepted: 9 January 2013
Published online: 26 February 2013

Abstract

Using molecular dynamics simulations, we exploit a charge-driven flip-flop that is composed several water molecules confined in a single-walled carbon nanotube. The flip-flop has two stable states and can be used to store state information. It can toggle between the two states within 2.5–3.5 ps (286 GHz–400 GHz). We reveal that the underlying mechanism is dominated by the interaction between the water molecules and nonuniform electric field generated by point charges. Namely, each water molecule tends to maintain its lowest electric energy by moving toward the location with the highest field strength. This flip-flop may be of value for molecular computing.