Trapping cold neutral atoms with an iron-core electromagnet

Abstract

We have developed an iron-core electromagnet and used it to trap neutral atoms. The magnetic field can be switched from a spherical quadrupole configuration to a Ioffe configuration within 2 ms. We load 2\(\)87Rb atoms from a vapor into a Magneto-Optical Trap (MOT) and transfer them into the purely magnetic trap with an efficiency of 95%. A strong radial compression is possible since we can generate quadrupole gradients up to 0.1 T/cm with an excitation current of 10 A (400 W of power consumption).