Hollow-beam atom tunnel

Yonho Song

Published Jan 1, 1999• 1 citation

Abstract

One of the more promising proposals for guiding and focusing neutral atoms involves dark hollow laser beams. When the frequency of the laser is detuned to the blue of resonance, the dipole force the atoms feel in the light confines them to the dark core where the atoms can be transported with minimal interaction with the light. The ability of the all-light atom guides to transport large number of ultracold atoms for long distances without physical walls leads to the possibility of a versatile tool for atom lithography, atom interferometry, atomic spectroscopy as well as for transporting and manipulating Bose-Einstein condensates. Furthermore since the atoms transported in all-light atom guides do not come into contact with matter, they can in principle be used to transport antimatter as well. In this work a hollow beam atom tunnel is demonstrated by guiding magneto-optically trapped ultracold cesium atoms with a hollow core laser beam. The 1mm diameter diffractionless hollow beam used to construct the atom tunnel was generated from a TEM00 mode diode laser at 852 nm using a series of axicons and simple lenses. The axicon generated hollow beam has a dark core extended for most of its diameter and

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