Lachaud L, Muraz B, Couto A, Raimond J-M, Brune M, Gleyzes S
<a href="https://ror.org/01h14ww21">Laboratoire Kastler Brossel</a>, Collège de France, CNRS, ENS-Université PSL, <a href="https://ror.org/02en5vm52">Sorbonne Université</a>, 11, place Marcelin Berthelot, 75005 Paris, France.
Phys Rev Lett. 2024 Sep 20;133(12):123202. doi: 10.1103/PhysRevLett.133.123202.
Rydberg alkaline earth atoms are promising tools for quantum simulation and metrology. When one of the two valence electrons is promoted to long-lived circular states, the second valence electron can be optically manipulated without significant autoionization. We harness this feature to demonstrate laser slowing of a thermal atomic beam of circular strontium atoms. By driving the main ion core 422 nm wavelength resonance, we observe a velocity reduction of 50 m/s without significant autoionization. We also show that a superposition of circular states undergoes very weak decoherence during the cooling process, up to the scattering of more than 1000 photons. This robustness opens new perspectives for quantum simulations over long timescales with circular atoms, while simultaneously cooling their motional state. It makes it possible to mitigate the harmful effects of unavoidable heating due to spin-motion coupling during a quantum simulation.
里德堡碱土原子是量子模拟和计量学中很有前景的工具。当两个价电子中的一个被激发到长寿命的圆态时，第二个价电子可以被光学操控而不会发生显著的自电离。我们利用这一特性展示了对圆态锶原子热原子束的激光减速。通过驱动主离子芯422纳米波长的共振，我们观察到速度降低了50米/秒，且没有显著的自电离。我们还表明，圆态的叠加在冷却过程中经历的退相干非常微弱，直至散射超过1000个光子。这种稳健性为使用圆原子进行长时间尺度的量子模拟开辟了新的前景，同时冷却它们的运动状态。这使得减轻量子模拟过程中由于自旋 - 运动耦合导致的不可避免的加热的有害影响成为可能。
