Matterwave interferometry for inertial sensing

用于惯性传感的 Matterwave 干涉测量

• 批准号: 1811645
• 金额: --
• 依托单位: University of Strathclyde
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1811645
• 关键词: Matterwave; interferometry; inertial; sensing

Navigation is a difficult problem, especially when access to the skies is restricted. Currently, most international travel by plane and ship relies on location through the GPS (Global Positioning Signal) signal, which is provided by a fleet of 24 satellites in orbit around Earth. If this signal is lost then, much like ancient sailors without sight of the stars, then the traveller very quickly loses track of their position. Given that GPS is owned and operated by one country, the USA, who can switch it off at any time and, furthermore, that it is open to hacking, it is clear that a means to have completely independent knowledge of location is required. The aim of this project is generate purely passive methods of tracking position with better than state-of-the-art sensitivity by the using of newly developed tools from atomic physics that harness the state-of-the-art in precision measurement. Atoms are strongly affected by inertial forces, the "pushing" effect that is felt when suddenly accelerating. This effect is already used to measure gravity, where measuring the time it takes for an object to fall a certain distance allows us to detect the force exerted by the mass of the Earth. Huge advances have been made in laser physics the last decades that allow measurement of positions with sub-atomic resolution through optical interferometry, which allows for similar increases in sensitivity to measurement of forces. The solution then is to use the well-known laws of Newton to integrate back the instantaneous velocity and position. However, the sensitivity required is extremely strict - an error of 10-5 m/s2 (one millionth of the acceleration due to gravity) results in a drift in position of 100 m in just one hour, and of approximately 50 km in one day. The solution is to use a quantum technology; the matter-wave interferometer. The ability to cool atoms down to only a few micronK using laser light has enabled some of the most spectacular developments in atomic physics in recent years. One of the most profound is the direct observation of the de Broglie wave nature of atoms and the subsequent achievement of a Bose-Einstein condensate (BEC), a state of matter where a cloud of atoms coalesce into a single quantum state [1]. The possibility of using interference of these coherent matter waves offers new levels of potential accuracy for measurement devices. A particular application of interest is that of inertial sensing with applications in quantum-based autonomous navigation devices. The Experimental Quantum Optics and Photonics group within the Physics Department at the University of Strathclyde have been leading in research in this area and have demonstrated new different methods for atom interferometry. In fact, members of this group produced the first BEC in the UK also the first in Scotland. This project will build on existing research at Strathclyde University in atom interferometry with coherent matter waves and work on ring-shaped guided traps to explore the possibilities for developing miniaturised technology for rotation sensing. Central for this will be integration with Strathclyde's microfabrication technology [2], which was recently developed for miniaturisation of the optical set-up for laser cooling setup.The goal of the project will be the demonstration of a matter-wave Sagnac interferometer in a ring-trap geometry. The system of a coherent matter wave confined in a ring trap is formally equivalent to the coherent optical field (laser) in a ring cavity known from the ring laser gyro [3]. The interesting difference, though, is that the sensitivity to phase rotation scales with the relativistic energy of the particle/wave involved. For atoms that is about eleven orders of magnitude larger than light. The project will build upon Strathclyde's unique experience in generating a toroidal, smooth trapping potential, where atomic waves can propagate in opposite directions (4,5).

导航是一个困难的问题，尤其是在限制天空的情况下。目前，大多数乘飞机和船舶的国际旅行都依赖于GPS（全球定位信号）信号的位置，该信号由地球周围轨道上的24颗卫星提供。如果丢失了这个信号，那么就像古老的水手看不到星星一样，旅行者很快就会失去他们的位置。鉴于GP是由一个国家拥有和运营的，美国可以随时关闭它，此外，它可以开放黑客入侵，很明显，需要对位置完全独立的一种方法。该项目的目的是通过使用原子理中新开发的工具来生成纯粹的被动跟踪位置方法，它比最先进的敏感性更好，从而利用了精确测量的最新工具。原子受到惯性力的强烈影响，突然加速时会感觉到的“推动”效果。这种效果已经用于测量重力，其中测量物体落下一定距离所需的时间使我们能够检测地球质量所施加的力。在过去的几十年中，激光物理学已经取得了巨大进展，可以通过光学干涉法测量以亚原子分辨率的位置，从而使对力测量的敏感性相似。然后，解决方案是利用牛顿众所周知的法律来融合瞬时速度和位置。但是，所需的灵敏度极为严格 - 误差为10-5 m/s2（由于重力造成的加速度的三分之一）导致一小时内漂移100 m，一天内约为50 km。解决方案是使用量子技术。物质波干涉仪。近年来，使用激光光冷却原子只能使用激光光冷却到几微米。最深刻的之一是直接观察原子的de broglie波性质，以及随后的玻色 - 因斯坦冷凝物（BEC）的实现，这是原子云合并为单个量子状态的物质[1]。使用这些相干物质波的干扰的可能性为测量设备提供了新的潜在准确性。感兴趣的一种特殊应用是惯性感测，其应用于基于量子的自主导航设备中的应用。 Strathclyde大学物理系内的实验量子光学和光子学组一直领先于该领域的研究，并证明了原子干扰法的新方法。实际上，该小组的成员在英国生产了第一个BEC，也是苏格兰的第一个BEC。该项目将基于Strathclyde University的原子干涉测量学与连贯的物质波，并在环形指导陷阱上工作，以探索开发用于旋转传感的小型化技术的可能性。中心将与Strathclyde的微加工技术集成[2]，该技术最近是用于针对激光冷却设置的光学设置而开发的。该项目的目的将是在环形几何形状中演示Matter-Wave Sagnac干涉仪。限制在环陷阱中的相干物质波的系统正式等同于从环激光器陀螺仪已知的环腔中的相干光场（激光）[3]。不过，有趣的区别在于，对相位旋转尺度的敏感性具有所涉及的粒子/波的相对论能量。对于比光大约11个数量级的原子。该项目将基于Strathclyde在产生环形，光滑的诱捕电位方面的独特经验，在该诱捕电位上，原子波可以朝相反的方向传播（4,5）。