Rydberg atom interferometry for antimatter gravity

原子的量子行为可以被用来进行物质波干涉计量学，即单个原子在两个不同状态的叠加中制备，然后在空间上分离，沿着两条不同的经典路径，然后重新组合进行干涉。原子干涉计量学的应用包括传感和测量场或加速度，例如由于重力。它通常是用基态原子进行的。然而，对于基态寿命短的奇异原子，如正电子素(一个电子和一个正电子的束缚态)，寿命较长的高激发里德堡态为克服短询问时间对测量精度的限制提供了一种潜在的解决方案。该项目的目标是在伦敦大学学院目前的初始设置的基础上，首次实现里德堡氦原子的全环原子干涉仪，以期将其扩展到里德堡正电子，以研究反物质在重力下的行为，以及这是否与物质不同。宇宙中物质和反物质之间的不对称性在粒子物理的标准模型中仍然是一个悬而未决的问题，量子技术为解决这些基本物理问题提供了新的机会。

The quantum behaviour of atoms can be exploited to perform matter wave interferometry, whereby single atoms are prepared in a superposition of two different states and then spatially separated to follow two different classical paths before being recombined to interfere. Atom interferometry has applications including the sensing and measurement of fields or accelerations, for example due to gravity. It is often performed with ground state atoms. However for exotic atoms with short lifetimes in the ground state, such as positronium (a bound state of an electron and a positron), highly excited Rydberg states with longer lifetimes offer a potential solution to overcome the limitations to measurement precision imposed by short interrogation times. This project aims build on current initial setups at UCL to realise a full loop atom interferometer with Rydberg helium atoms for the first time, with a view to extending this to Rydberg positronium to investigate the behaviour of antimatter under gravity, and whether this differs from matter. The asymmetry between matter and antimatter in the Universe remains an open question in the standard model of particle physics, with quantum technologies providing new opportunities to address such fundamental physics questions.