Laser trapping, cooling and sensing of atoms and molecules with nanostructured surfaces

直到最近，原子和分子的研究和操纵几乎总是在移动的和高能物质上进行的。然而，就像在许多领域一样，如果受试者被限制和固定，测量和操纵可以以更高的精度和技巧进行。尽管有许多技术专注于最慢的物种，大多数测量和几乎所有的原子和分子的反应都是在热分布上进行的。基础研究、加工和传感的结果是有限的相互作用时间和移动的、随机取向的样品。激光镊子和多普勒冷却技术利用光子流施加的辐射压力来减慢和捕获有限范围的原子。原子被固定下来，几乎静止不动，可以前所未有地进行检查和操纵。决定性的量子力学支配着它们的行为;碰撞是可逆的;分子可以形成，然后用精密的遥控器打破。即使在这些早期，已经提出了广泛的技术开发，从计量到传感和信息处理。不幸的是，只有单一的，微小的陷阱通常是可能的，而且，因为冷却过程只适用于有限范围内的物种，大多数原子和所有进入陷阱的分子保留足够的动能离开后不久，我们建议使用纳米纤维技术，在南安普顿开发，生产凹面镜阵列的焦点，当用激光照射时，每个将成为一个微小的陷阱。这样的阵列提供存储比一个单一的陷阱更多的物种，每个陷阱可以很容易地在显微镜下区分。将物种限制在表面的几个波长内允许新的相互作用和技术，这些新的相互作用和技术增加了陷阱强度并提高了物种可以被检测和观察的灵敏度。表面的范围和接近程度也提出了令人兴奋的新机制，可以冷却比以前可能的更广泛的物种。这项研究将研究一系列的捕获和冷却几何形状，最终目标是将目前仅限于少数元素的原子样品的控制扩展到分子。

The study and manipulation of atoms and molecules has until recently nearly always been performed upon mobile and energetic species. Yet, as in so many fields, measurement and manipulation could be performed with far greater precision and finesse if the subject were confined and immobilized. Despite many techniques which focus on the slowest species, most measurements and virtually all reactions of atoms and molecules are performed on thermal distributions. The consequences for fundamental studies, processing and sensing are a finite interaction time and a moving, randomly orientated sample.Laser tweezers and Doppler cooling techniques use the radiation pressure exerted by a stream of photons to slow and capture a limited range of atoms. Pinned down and virtually stationary, the atoms can be examined and manipulated like never before. Deterministic quantum mechanics dominates their behaviour; collisions are reversible; and molecules can be formed and then broken with exquisite remote control. Even in these early days, a wide range of technological exploitations has been proposed, from metrology to sensing and information processing. Unfortunately, only single, tiny traps are usually possible, and, because the cooling process only works with a limited range of species, most atoms and all molecules that enter the trap retain enough kinetic energy to leave shortly after.We propose to use nanofabrication techniques, developed in Southampton, to produce arrays of concave mirrors whose foci, when illuminated with a laser, will each become a tiny trap. Such arrays offer to store many more species than a single trap, and each trap can easily be distinguished under a microscope. Confining species within a few wavelengths of a surface allows new interactions and techniques that increase the trap strength and enhance the sensitivity with which the species may be detected and observed. The extent and proximity of the surface also presents exciting new mechanisms for cooling a far wider range of species than previously possible. This research will investigate a range of trapping and cooling geometries, with the ultimate aim of extending to molecules the control currently limited to atomic samples of just a small number of elements.