Atomic transitions satisfying $F_e - F_g = ΔF = \pm 2$ (where $F_e$ stands for excited and $F_g$ stands for ground state) of alkali atoms have zero probability in zero magnetic field (they are so-called "forbidden" transitions) but experience a large probabilty increase in an external magnetic field. These transitions are called magnetically induced (MI) transitions. In this paper, we use for the first time the $σ^+$ ($Δm_F~=~+1$) MI transitions $F_g = 3 \rightarrow F_e = 5$ of {Cesium} as probe radiation to form EIT resonances in strong magnetic fields (1 - 3 kG) while the coupling radiation frequency is resonant with $F_g=4\rightarrow F_e=5$ $σ^+$ transitions. The experiment is performed using a nanometric-thin cell filled with Cs vapor and a strong permanent magnet. The thickness of the vapor column is 852 nm, corresponding to the Cs $D_2$ line transition wavelength. Due to the large frequency shift slope of the MI transitions ($\sim$ 4 MHz/G), it is possible to form contrasted and strongly frequency-shifted EIT resonances. Particularly, a strong 12 GHz frequency shift is observed when applying an external magnetic field of $\sim$ 3 kG. Preliminary calculations performed considering Doppler-broadened three level systems in a nanocell are in reasonable agreement with the experimental measurements.
Measurement of the parity violating 6S-7S transition amplitude in cesium achieved within 2 \times 10^{-13} atomic-unit accuracy by stimulated-emission detection
我们利用受激发射的不对称放大过程，为测量高度禁戒原子跃迁中的宇称破坏（PV）提供了一种新颖的方法。该方法涉及的手征，瞬态，光学增益的铯蒸汽上的7S-6 P_{3/2}过渡，探测后，它是由一个强烈的，线性偏振，共线激光激发，调谐到共振的一个超精细线的禁止6S-7S过渡在纵向电场。我们在这里报告说，与我们以前的结果相比，一秒测量灵敏度增加了3.5倍，随后统计准确度降低了3.5倍[J. Guéna et al.，物理修订版信函90，143001（2003）]。决定性的改进，设置包括增加重复率，更好地消光的探测光束在年底的探测脉冲，并为第一次，据我们所知，以下内容：一个偏振倾斜放大器，准抑制光束反射的细胞窗口，和一个Cs细胞与导电窗口。我们还提出了系统效应的实时测试，数据的一致性检查，以及原子信号中原子所见电场的1%准确度测量。在七个不同的蒸汽电池中进行的PV测量在统计误差范围内一致。在我们目前的相对统计精度为2.6%的范围内，我们目前的结果与更精确的Boulder结果是相容的，对应于E_1^{pv}的2 \times 10^{-13}原子单位的不确定度。进一步测量的理论动机强调，我们给出了一个简短的概述，最近的建议，将允许的不确定性降低到0.1%的水平，通过创造条件，不对称放大更大。
Angle-of-Arrival Determination of Radio-Frequency Fields Using Stark-Shifted Rydberg-EIT Spectra
National Institute of Standards and Technology（美国国家标准与技术研究院）；Department of Electrical, Computer, and Energy Engineering, University of Colorado, Boulder（科罗拉多大学博尔德分校电气、计算机与能源工程系）
