Low-SWaP Chip-Scale Atomic Beam Source

A high-brightness narrow-velocity-distribution atom source plays a critical role in enabling high performance atomic clocks, inertial sensors, and quantum information devices. Laser cooling technology currently used to produce collimated atomic beams with a narrow velocity distribution involves large size and complex devices due to optical constraints, preventing realization of miniaturized atomic devices with low size, weight, and power (SWaP) for practical uses. In this project, StethX Microsystems Inc. (StethX) in collaboration with the Georgia Institute of Technology (Georgia Tech) will develop a low-SWaP chip-scale filtered Rubidium (Rb) atomic beam source with superior brightness and narrow velocity distribution based on a silicon micro-channel collimator technology, which uses no lasers and will be suitable for scalable batch fabrication and easy integration in miniaturized atomic sensors and devices. The atomic beam source chip will be based on a planar silicon collimator technology developed by our team at Georgia Tech, which is fabricated using semiconductor micromachining process that enables sub-micron precision dimensions defined by photolithography with high design flexibility. The atomic beam source device will be self-contained with a rubidium source cavity, planar micro-collimators, a self-sustained vacuum drift cavity, and integrated micro heaters for temperature control. Materials and designs compatible with wafer-level micro-fabrication processes will be investigated to enable scalable manufacturing of the atomic beam chip. In Phase I, we will optimize the micro-collimator dimensions and incorporate embedded temperature control element in the design to achieve desired atomic flux with more precise velocity control and in a more compact form-factor. Monte-Carlo and finite element simulations, along with short loop testing using our existing proof-of-concept devices will be done to verify the performance and feasibility of the technology. Based on the optimized design, a fabrication process flow will be defined with suitable foundries identified for Phase II prototype fabrication and eventually mass production.