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 ${\text{∼10}}^8\hspace{0.17em}{\mathrm{A/cm}}^{\mathrm{2}}$ and power dissipation $\text{∼10\hspace{0.17em}}{\mathrm{kW/cm}}^{\mathrm{2}},$ and they produce magnetic fields to 0.3 T and gradients to ${10}^3\hspace{0.17em}\mathrm{T/cm}.$ The micro-electromagnet mirror was used to deflect a beam of metastable helium atoms at grazing angles $\text{∼0.5\hspace{0.17em}}\mathrm{mrad}.$