Dipole rectification in an oscillating electric fieldA. Pototsky1, N. B. Janson1, F. Marchesoni2, 3 and S. Savel'ev3
1 School of Mathematics, Loughborough University - Loughborough LE11 3TU, UK, EU
2 Dipartimento di Fisica, Università di Camerino - I-62032 Camerino, Italy, EU
3 Department of Physics, Loughborough University - Loughborough LE11 3TU, UK, EU
received 14 September 2009; accepted in final form 16 October 2009; published November 2009
published online 13 November 2009
Directed transport of a neutral dimer driven by an ac electric field on a one-dimensional asymmetric substrate is demonstrated. We specialize on the case of a short elastic dimer formed by two bound equal masses carrying opposite charges, i.e., a dipole. The combination of ac drive and binding potential induces a net dipole current (strictly zero for a rigid dimer), which can be optimized by tuning the temperature and the driving frequency with distinct activation energies. Under appropriate operating conditions, a dimer can get rectified more efficiently than its constituents set free, thus implying that particle pairing can actually enhance the ratchet effect.
05.60.-k - Transport processes.
66.10.C- - Diffusion and thermal diffusion.
© EPLA 2009