AI 中文总结
本研究针对准布拉格区原子干涉测量中激光冷却原子的动量态分离难题，采用拉曼光谱对原子态演化频闪采样，表征双光子及最优控制增强的多光子布拉格跃迁，匹配动力学模拟并完成6___k布拉格重力仪的动量光谱分析。
AI 中文摘要
准布拉格区是大动量转移原子干涉测量的良好折中方案，可扩大干涉区域，同时抑制非期望态的布居。然而，使用激光冷却原子而非亚反冲速度分布的超冷原子时，通过标准飞行时间法分离动量态颇具挑战性。为克服该局限，我们采用拉曼光谱对探测激光脉冲期间动量空间的原子态演化进行频闪采样。我们定量表征了原子光学的双光子（2___k）和多光子（6___k）布拉格跃迁，其中多光子布拉格跃迁可通过最优控制协议增强。我们将观测到的原子态动力学与模拟结果紧密匹配，最终在6___k布拉格重力仪中对输出态进行动量光谱分析。
英文摘要
Quasi-Bragg regime is a good compromise for large-momentum-transfer atom interferometry, allowing for scaling up the interferometric area, while constraining the population of unwanted states. Separation of momentum states via standard time of flight methods, however, can be challenging when using laser-cooled atoms, rather than ultracold atoms with sub-recoil velocity distribution. To overcome this limit, we use Raman spectroscopy for stroboscopic sampling of the atomic state evolution in momentum space during the interrogating laser pulses. We quantitatively characterize atom optics employing two-photon (2___k) and multi-photon (6___k) Bragg transitions, the latter being optionally enhanced with optimal control protocol. We closely match the observed dynamics of the atomic state with simulations. Finally, we perform momentum spectroscopy of the output states in a 6___k Bragg gravimeter.
