Eur. Phys. J. D 64, 85-101 (2011)
https://doi.org/10.1140/epjd/e2011-20208-y

Regular Article

Novel electrodynamic trapping mechanism for neutral, polar particles

Wesleyan University, Middletown, CT 06459-0155, USA

^a e-mail: rblumel@wesleyan.edu

Received: 9 April 2011
Published online: 2 August 2011

Abstract

A conceptually new trapping mechanism for neutral, polar particles is introduced and discussed. Unlike existing mechanisms that are based on oscillating saddle-point potentials or rotating electric dipole fields, the new mechanism is based on a superposition of ac and dc electric monopole fields that dynamically generate a minimum of the effective ponderomotive potential in which the particles are trapped. Extensive numerical simulations of the dynamics and the stability properties of trapped HC₁₇N molecules and ferroelectric rods (made of barium titanate or croconic acid crystals) prove the validity of the new mechanism. The examples show that the same mechanism is applicable to the trapping of macroscopic as well as microscopic particles. The numerical results are backed by a physical pseudo-potential picture and an analytical stability analysis that provide physical insight into why and how the new mechanism works. A semi-quantum, Born-Oppenheimer-type calculation that treats the intrinsic rotational degree of freedom of HC₁₇N quantum mechanically is also presented. A detailed discussion of engineering aspects shows that laboratory implementation of the new mechanism is within current technological reach.