多模1064nm光纤激光器实现一维远失谐光晶格

采用1064 nm多模30 W连续光纤激光器, 搭建了一个周期为25 μm的一维远失谐光学晶格势场. 对铷原子进行磁光阱装载和偏振梯度冷却, 实现了铷冷原子团在光晶格中的装载. 借助于短程飞行时间法, 测量晶格中冷原子温度为20 μK, 为下一步实现量子信息存储实验奠定了基础.

One-dimensional far-detuned optical lattice realized with a multimode 1064 nm laser

For a quantum memory to be useful as a quantum repeater, a long coherence time is a crucial requirement. In recent years, the most commonly explored medium for quantum storage has been atomic gases. We report an experiment to realize a quantum memory based on an Rb atomic ensemble in a one-dimensional far-detuned optical lattice. A multimode 30 W continuous wave fiber laser was used to construct a travelling wave lattice with a period of 25 μm. The Rb atoms were loaded into a magneto-optical-trap, which was then adjusted to optimize the polarization gradient cooling. To trap the cooled atoms, we turned on a laser which has a wavelength of 1064 nm and therefore is red-detuned from the resonance frequencies of D₁ and D₂ transitions of ⁸⁷Rb atoms. By taking the short-distance time-of-flight image the temperature of the atoms was found to be about 20 μK. This system will provide a foundation for future quantum information storage studies.