Sorbonne Université, Observatoire de Paris, Université PSL, CNRS, LERMA, F-75005, Paris, France.
Rep Prog Phys. 2018 Sep;81(9):094401. doi: 10.1088/1361-6633/aac9e9. Epub 2018 Jun 4.
Probing an atomic resonance without disturbing it is an ubiquitous issue in physics. This problem is critical in high-accuracy spectroscopy or for the next generation of atomic optical clocks. Ultra-high resolution frequency metrology requires sophisticated interrogation schemes and robust protocols handling pulse length errors and residual frequency detuning offsets. This review reports recent progress and perspective in such schemes, using sequences of composite laser-pulses tailored in pulse duration, frequency and phase, inspired by NMR techniques and quantum information processing. After a short presentation of Rabi technique and NMR-like composite pulses allowing efficient compensation of electromagnetic field perturbations to achieve robust population transfers, composite laser-pulses are investigated within Ramsey's method of separated oscillating fields in order to generate non-linear compensation of probe-induced frequency shifts. Laser-pulses protocols such as hyper-Ramsey, modified hyper-Ramsey, generalized hyper-Ramsey and hybrid schemes as auto-balanced Ramsey spectroscopy are reviewed. These techniques provide excellent protection against both probe induced light-shift perturbations and laser intensity variations. More sophisticated schemes generating synthetic frequency-shifts are presented. They allow to reduce or completely eliminate imperfect correction of probe-induced frequency-shifts even in presence of decoherence due to the laser line-width. Finally, two universal protocols are presented which provide complete elimination of probe-induced frequency shifts in the general case where both decoherence and relaxation dissipation effects are present by using exact analytic expressions for phase-shifts and the clock frequency detuning. These techniques might be applied to atomic, molecular and nuclear frequency metrology, Ramsey-type mass spectrometry as well as precision spectroscopy.
在不干扰原子共振的情况下探测原子共振是物理学中一个普遍存在的问题。这个问题在高精度光谱学或下一代原子光学钟中至关重要。超高分辨率频率计量需要复杂的询问方案和稳健的协议，以处理脉冲长度误差和残余频率失谐偏移。本综述报告了使用受 NMR 技术和量子信息处理启发的复合激光脉冲序列在这些方案中的最新进展和观点，这些脉冲序列在脉冲持续时间、频率和相位上进行了精心设计。在简要介绍了 Rabi 技术和类似于 NMR 的复合脉冲之后，这些复合脉冲可以有效地补偿电磁场干扰，以实现稳健的群体转移，然后在 Ramsey 的分离振荡场方法中研究了复合激光脉冲，以产生对探测诱导的频率偏移的非线性补偿。综述了诸如超 Ramsey、改进超 Ramsey、广义超 Ramsey 和混合方案（如自动平衡 Ramsey 光谱学）等激光脉冲协议。这些技术提供了对探测诱导的光移干扰和激光强度变化的出色保护。提出了更复杂的产生合成频率偏移的方案。即使存在由于激光线宽引起的退相干，它们也可以减少或完全消除对探测诱导的频率偏移的不完全校正。最后，提出了两种通用协议，它们通过使用相位偏移和时钟频率失谐的精确解析表达式，在存在退相干和弛豫耗散效应的一般情况下，完全消除了探测诱导的频率偏移。这些技术可应用于原子、分子和核频率计量学、 Ramsey 型质谱以及精密光谱学。
