Micro-electromagnets for atom manipulation

Abstract

Micro-electromagnets for atom manipulation have been constructed, including magnetic mirrors (serpentine patterns) and traps (circular patterns). They consist of planar micron-scale Au wires on sapphire substrates fabricated using lithography and electroplating. At liquid nitrogen or helium temperatures in vacuum the wires support currents of several amperes with current density ∼108 A/cm2 and power dissipation ∼10 kW/cm2, and they produce magnetic fields to 0.3 T and gradients to 103 T/cm. The micro-electromagnet mirror was used to deflect a beam of metastable helium atoms at grazing angles ∼0.5 mrad.

Atom chips: Fabrication and thermal properties

“…The fabrication process preferred by groups working in the field is to grow thick wires from a thin patterned layer using electroplating [13,14,15], which allow large currents for trapping and manipulating the atoms.…”

Reconstruction of a Cold Atom Cloud by Magnetic Focusing

“…One new direction is the microfabricated electromagnet mirror [19]. Its ultimate flatness may prove to be better than one can achieve with recorded media, although it is at too early a stage of development to know.…”

Perspectives of ultracold atoms trapped in magnetic micro potentials

“…At then realistic values of b=1 T/cm, ω reduces to and the radial frequency must now be smaller than of In practice, the current conductors are realized either by simple copper or aluminum wires [3,11] or by micro fabricated gold, copper, or silver conductors. Micro fabrication, in principle, allows for extremely narrow conductors on the order of a micrometer and below, with a thickness of only several hundred nanometers and correspondingly large gradients of 100 T/cm and more [12,9,13,14,15]. However up to now, typical experiments were usually carried out with much wider conductors on the order of several 10 micrometers where micro fabrication is simply a method for making conductors with a well defined geometry.…”