Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
DEVCOM U.S. Army Research Laboratory, Adelphi, MD, 20783, USA.
Nat Commun. 2023 May 29;14(1):3080. doi: 10.1038/s41467-023-38818-6.
Cold atoms are important for precision atomic applications including timekeeping and sensing. The 3D magneto-optical trap (3D-MOT), used to produce cold atoms, will benefit from photonic integration to improve reliability and reduce size, weight, and cost. These traps require the delivery of multiple, large area, collimated laser beams to an atomic vacuum cell. Yet, to date, beam delivery using an integrated waveguide approach has remained elusive. Here we report the demonstration of a Rb 3D-MOT using a fiber-coupled photonic integrated circuit to deliver all beams to cool and trap > 1 ×10 atoms to near 200 μK. The silicon nitride photonic circuit transforms fiber-coupled 780 nm cooling and repump light via waveguides to three mm-width non-diverging free-space cooling and repump beams directly to the rubidium cell. This planar, CMOS foundry-compatible integrated beam delivery is compatible with other components, such as lasers and modulators, promising system-on-chip solutions for cold atom applications.
冷原子在精密原子应用中很重要，包括计时和传感。用于产生冷原子的三维磁光阱（3D-MOT）将受益于光子集成，以提高可靠性并减小尺寸、重量和成本。这些陷阱需要将多个大面积准直激光束传输到原子真空室中。然而，迄今为止，使用集成波导方法进行光束传输仍然难以实现。在这里，我们报告了使用光纤耦合光子集成电路演示 Rb 3D-MOT 的情况，该集成电路可将所有光束传输到冷却和捕获 > 1×10 个原子的近 200μK 温度。氮化硅光子电路通过波导将光纤耦合的 780nm 冷却和重泵浦光转换为三条宽度为 3mm 的非发散自由空间冷却和重泵浦光束，直接传输到铷原子室。这种平面、与 CMOS 兼容的集成光束传输与其他组件（如激光器和调制器）兼容，为冷原子应用提供了片上系统解决方案的前景。
