Acta Physica Sinica

Controllable doublewell optical trapfor cold atoms or molecules

纪宪明 Ji Xianming, Yin Jianping, (1)华东师范大学物理系，光谱学与波谱学教育部重点实验室，上海　200062; (2)华东师范大学物理系，光谱学与波谱学教育部重点实验室，上海　200062(南通大学物理系，南通　226007

Published Jan 1, 2004• 6 citations

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Abstract

In this paper, we propose a novel scheme to form a controllable doublewell opt i cal trap for cold atoms or molecules by using a system composed of a binary π phase plate and a lens illuminated by a plane light wave. We calculate the int ensi ty distribution of the doublewell trap, and study the evolution process of th e optical trap from two wells to a single well, and derive the analytical relation between the characteristic parameters of the doublewell trap (includi ng g eometric parameters, the intensity distributions, intensity gradients and their curvatures) and the parameters of optical system. We find that our doublewell trap can be continuously changed into a singlewell trap by moving the πphas e pl ate along the x direction, and the relation between the distance of the trap ping centers of the two wells and the moving distance of the πphase plate is obt ain ed by data fitting. In addition, our doublewell scheme is not only simple and c onvenient, but also has some important and wide applications in the fields of at omic physics, atom optics, molecule optics and quantum optics and so on.

DOI: 10.7498/aps.53.4163

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