compact Cold-Atom Sources (cCAS)

紧凑型冷原子源 (cCAS)

基本信息

批准号：
EP/R001685/1
负责人：
Christopher Foot
金额：
$ 25.04万
依托单位：
University of Oxford
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2017
资助国家：
英国
起止时间：
2017 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FR001685%2F1
关键词：
compact Cold Atom Sources cCAS

项目摘要

We shall develop compact cold-atom sources for the alkali metals rubidium, caesium and potassium; and for the alkaline-earth metal strontium (Sr). These are very suitable for a range of applications in quantum technology and a components in the construction of apparatus for scientific research more broadly. Magneto-optical traps (MOTs) can capture slow atoms directly from an atomic vapour at room temperature to provide a very convenient source of cold atoms. We have used an arrangement of four triangular mirrors arranged as a pyramid inside the vacuum region to make a MOT in three separate experiments over the years. Recently we developed an improved design that is more compact and adjustable than other sources. A patent application covering the innovative features of this pyramid-MOT was applied for in April 2016 and we are constructing a prototype working with rubidium (Rb). We will develop this into a commercial product integrated with a laser system produced by M Squared Lasers (MSL). The company's titanium-doped sapphire lasers provide a high power, relative to other tuneable lasers, and unmatched stability. We shall make full use of the available laser power by tailoring the size of the mirrors and enclosing vacuum chamber to produce a high flux of atoms. This will a give strong signals and high repetition rate of measurements in instruments such as atomic interferometers which as the basis of the quantum technology used in gravimeters, gyroscopes etc. This device can laser cool the other alkali metal atoms Cs and K, and light at all the wavelengths required is available from MSL. Compact and reliable cold-atom sources are of themselves a useful device that can be sold in the scientific equipment market that constitutes much of MSL's present sales. While working on compact cold-atom sources we have noted the rapidly increasing interest in using cold strontium atoms for optical-lattice clocks, matter-wave interferometers and experiments with ultracold quantum gases. Strontium has intrinsic advantages such as rapid laser cooling, insensitivity to external magnetic fields and, for some isotopes, inter-atomic collisions are almost negligible. However working with cold Sr atoms much more technically demanding than Rb. In the traditional approach to laser cooling this species Sr atoms pass along the axis of a tapered solenoid (so-called Zeeman slowing developed in the 1980s) and many more laser wavelengths are required than for an alkali metals (Rb etc.) - up to 6 wavelengths for a Sr optical-lattice clock. However the availability of reliable lasers (from MSL) will make it possible to use Sr in products in the short term (within 5 years). Reportedly there have been attempts to make more compact sources of cold Sr using approaches similar to those for Rb but, for reasons explained in the proposal, a different method is more feasible. Our approach combines aspect of Zeeman slowing with long magnets with the compactness of in-vacuum mirrors (as in our pyramid design). In a further step we can develop this into a pulsed source that allows rapid loading of a high number of atoms (e.g. in 0.01 s) but with a much reduced flux of atoms during the measurement period (e.g. 1 s for some clocks). This mode of operation, with a pulsed valve, conserves atoms so that the oven does not need frequent reloading which is inconvenient especially for a field-deployed interferometer. The team in Oxford are not using Sr (although the PI has in the past) but the expertise is available to build the novel design (with features that we can patent, as in the work on Rb). The optimum outcome would provide a competitive edge for a product manufactured by MSLs. Licensing, or other, will be managed through Oxford University Innovation Ltd (as for the cold-atom source of Rb) to protect the technology and ensure that it remains part of a UK-based industry.

我们将为碱金属rubidium，Cesium和Potassium开发紧凑的冷原子源；以及碱性金属锶（SR）。这些非常适合在量子技术中的一系列应用以及更广泛的科学研究设备中的组成部分。磁光陷阱（MOTS）可以在室温下直接从原子蒸气中捕获慢性原子，以提供非常方便的冷原子来源。多年来，我们使用了一个排列为金字塔的四个三角形镜子的布置，以在三个单独的实验中进行MOT。最近，我们开发了一种改进的设计，比其他来源更紧凑，更可调。 2016年4月，应用了涵盖该金字塔模具创新特征的专利应用程序，我们正在构建与Rubidium（RB）一起工作的原型。我们将将其开发为与M平方激光器（MSL）产生的激光系统集成的商业产品。相对于其他可调激光器和无与伦比的稳定性，该公司的钛掺杂蓝宝石激光器提供了高功率。我们将通过调整镜子的大小并封闭真空室以产生高原子通量来充分利用可用的激光功率。这将为诸如原子干涉仪之类的仪器中的强烈信号和高度重复速率，作为重量计，陀螺仪，陀螺仪等量子技术的基础等，该量子的基础。该设备激光可以使其他碱金属原子CS和K冷却，并在所有需要的波长中获得光线。紧凑而可靠的冷原子资源本身就是一种有用的设备，可以在构成MSL目前销售的大部分科学设备市场中出售。在处理紧凑的冷原子源时，我们注意到使用冷锶原子用于光晶格，物质波干涉仪和超电量子气体实验的兴趣迅速增加。锶具有固有的优势，例如快速激光冷却，对外部磁场不敏感，对于某些同位素，原子间碰撞几乎可以忽略不计。但是，与冷SR原子的合作在技术要求上比RB更高。在传统的激光冷却方法中，该物种SR原子沿着锥形电磁阀的轴（所谓的Zeeman在1980年代发展而发展），并且比碱金属（RB等）需要更多的激光波长 - 对于SR光学效果最多6个波长。但是，可靠的激光器（来自MSL）的可用性将使在短期内（5年内）在产品中使用SR成为可能。据报道，已经尝试使用类似于RB的方法来制造更紧凑的冷SR来源，但出于提案中解释的原因，另一种方法更可行。我们的方法将Zeeman的方面与长磁铁放慢速度以及空中镜子的紧凑性（如我们的金字塔设计中）。在进一步的步骤中，我们可以将其发展为脉冲源，该脉冲源可以快速加载大量原子（例如，0.01 s），但在测量期间（例如，某些时钟为1 s），原子的通量却大大减少。这种具有脉冲阀的操作方式可以保存原子，因此烤箱不需要频繁的重新加载，这是不便的，尤其是对于野外部署的干涉仪。牛津的团队不使用SR（尽管PI过去曾经使用过），但是专业知识可用于构建新颖的设计（具有我们可以专利的功能，如RB的工作）。最佳结果将为MSL生产的产品提供竞争优势。许可或其他将通过牛津大学创新有限公司（至于RB的冷原子来源）进行管理，以保护该技术，并确保其仍然是英国行业的一部分。