System Stability Optimization and Gate Operations in a Compact Cryogenic Ion Trap Setup

We describe one- and two-qubit operations in a compact ion trapping system at cryogenic temperature. A low-vibration closed-cycle cryostat is utilized with all optics mounted on machined plates for operations with higher stability. We use Sandia High-Optical Access (HOA) surface traps and install the trap into a compact package, enabling easier system integration and characterization. The surface trap is mounted on a ceramic pin grid array (CPGA) package and covered with a copper lid with a meandering channel for differential pumping. The whole package is cooled down to a base temperature of 7K. We set up a Michelson interferometer to characterize and optimize the vibrations from the cryostat to the ion trap with respect to control lasers and give a quantitative analysis on the effect of vibrations on gate fidelity. We show the latest result of M{\o}lmer-S{\o}rensen gate fidelity with an analysis of the source of errors, which are dominated by motional decoherence.