Precision measurements of cold atom - hot gas collisions.

激光冷却和俘获原子已经彻底改变了基础科学和应用技术。事实上，冷原子现在是最精确的时钟的基本组成部分，它们可以用来制造人类已知的最灵敏的重力计和加速度计。这些技术通过革新计时、通信、遥测和惯性制导技术，极大地影响了社会。这种技术影响的一个无处不在的例子是全球定位系统，它依赖于基于卫星的原子钟的同步。*这项研究计划提案的目标是使用冷的、被捕获的原子来测量在真空环境中被捕获的原子和热的背景气体之间的碰撞。这些测量将使我们能够区分弹性、非弹性和反应性碰撞过程，从而能够研究粒子之间的远距离相互作用。这项工作的一个好处是，它提供了基于疏水阀损失测量来定义高真空和超高真空范围的压力标准的机会。被困在浅电势中的冷原子是在真空中探测其他粒子的近乎理想的候选者。当一个粒子穿过被困原子的碰撞截面时，一些动量被传递给静止的原子。碰撞是通过从陷阱中失去原始“传感器”原子来检测的。这些测量不受传感器退化或校准漂移的影响，因为碰撞是由粒子不变的物理特性控制的。*拟议的研究计划将扩展我与Kirk Madison （UBC）的合作工作，并导致高精度碰撞测量的实现，并产生新的压力测量技术。一个重要的影响预计是创建了特高压范围内的第一个主要压力标准。研究和开发计划可以扩展到生产一种冷原子压力装置，能够取代现有的基于电离的真空计量，北美每年的市场估计为1.7亿美元。因此，拟议的研究计划将是知识动员的有效形式，从而为加拿大带来商业上有用的创新和经济效益。

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.