Trapping ultracold gases near cryogenic materials with rapid reconfigurability

We demonstrate an atom chip trapping system that allows the placement and high-resolution imaging of ultracold atoms within microns from any <= 100 mu m-thin, UHV-compatible material, while also allowing sample exchange with minimal experimental downtime. The sample is not connected to the atom chip, allowing rapid exchange without perturbing the atom chip or laser cooling apparatus. Exchange of the sample and retrapping of atoms has been performed within a week turnaround, limited only by chamber baking. Moreover, the decoupling of sample and atom chip provides the ability to independently tune the sample temperature and its position with respect to the trapped ultracold gas, which itself may remain in the focus of a high-resolution imaging system. As a first demonstration of this system, we have confined a 700-nK cloud of 8 x 10(4) Rb-87 atoms within 100 mu m of a gold-mirrored 100-mu m-thick silicon substrate. The substrate was cooled to 35K without use of a heat shield, while the atom chip, 120 mu m away, remained at room temperature. Atoms may be imaged and retrapped every 16 s, allowing rapid data collection. (C) 2013 AIP Publishing LLC.