Two-wire guides and traps with vertical bias fields on atom chips

Abstract

We present atom chip traps and guides created by a combination of two current-carrying wires and a bias field pointing perpendicular to the chip surface. These elements can be arranged in any orientation on the chip surface. We study loading schemes for the traps and present a detailed study of the guiding of thermal atomic clouds in an omnidirectional matter waveguide along a $25\text{−}\mathrm{mm}$-long curved path at various atom-surface distances $(35–450\mu \mathrm{m})$. An extension of the scheme for the guiding of Bose-Einstein condensates is outlined. Such a concept enables utilizing the full two-dimensional surface of the chip.