Microwave Atom Chip for Ultracold Trapped Atom Interferometery

We present progress on the development of a microwave atom chip to be used for trapped atom interferometry using spin-specific AC Zeeman potentials. The chip uses three parallel microstrip transmission lines to generate microwave ACZ traps.  Efficient DC-10 GHz coupling of microwave signals onto the chip is based on a tapered microstrip wedge interface design. We have started micro fabrication of chip components and have worked to characterize the Aluminum Oxynitride substrate used in our atom chip design. Furthermore, we are developing microwave amplifier systems to generate a microwave lattice which will enable Ramsey interferometry with spatially separated ⁸⁷Rb spin states. We have already demonstrated the effect of microwaves on ⁸⁷Rb atoms in a uniform magnetic field before transporting them to the chip. This work furthers the development of our precision measurement capabilities for gravimetry and possible measurements of the Casimir-Polder force and submillimeter gravity. This work is supported by NSF.