Precision measurements of cold atom - hot gas collisions.

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Laser cooled and trapped atoms have revolutionized basic science and applied technologies. Indeed, cold atoms are now the fundamental building block for the most precise clock that can be made, and they can be used to create the most sensitive gravitometer and accelerometer known to man. These technologies have dramatically impacted society by revolutionizing time-keeping, communication, telemetry, and inertial guidance technologies. A ubiquitous example of the impact of this technology is the Global Positioning System which relies on the synchronization of satellite-based atomic clocks. This research program proposal, has the goal of using cold, trapped atoms for measuring collisions between the trapped atoms and hot, background gases in the vacuum environment. These measurements will allow us to distinguish between elastic, inelastic, and reactive collision processes, enabling the study of the long range interactions between particles. One benefit of this work is that it affords the opportunity to define a pressure standard for the high-vacuum and ultra-high vacuum ranges based on trap loss measurements. A cold atom, trapped in a shallow potential, is a near ideal candidate to detect other particles in a vacuum. When a particle passes through the collision cross-section of the trapped atom, some momentum is transferred to the stationary atom. The collision is detected via the loss of the original “sensor” atom from the trap. These measurements are not subject to sensor degradation or calibration drift since the collisions are governed by the immutable physical properties of the particles. The proposed research program will extend my collaborative work with Kirk Madison (UBC) and lead to the realization of high precision collision measurements and produce a new pressure measurement technology. A significant impact is expected to be the creation of the first primary standard for pressure in the UHV range. The research and development program can be extended to produce a cold atom-based pressure device capable of superseding the existing, ionization-based vacuum metrology, a market estimated at $170 million per year in North America. Therefore, the proposed research program will be an effective form of knowledge mobilization resulting in commercially useful innovation and economic benefit for Canada.