On the Zeeman effect on Rydberg atoms

V. E. Chernov, Dmitrii L. Dorofeev, B. A. Zon

Jingxu Bai, Rong Song, Xijun Li +4 more

We report on high-resolution microwave spectroscopy of cesium Rydberg $(n+2){D}_{5/2}\ensuremath{\rightarrow}n{F}_{J}$ transitions in a cold atomic gas. Atoms laser-cooled and trapped in a magnetic-optical trap are prepared in the $D$ Rydberg state using a two-step laser excitation scheme. A microwave field transmitted into the chamber with a microwave horn drives the Rydberg transitions, which are probed via state selective field ionization. Varying duration and power of the microwave pulse, we observe Fourier sideband spectra as well as damped, on-resonant Rabi oscillations with pulse areas up to $\ensuremath{\gtrsim}3\ensuremath{\pi}$. Furthermore, we investigate the Zeeman effect of the clearly resolved $n{F}_{J}$ fine-structure levels in fields up to 120 mG, where the transition into $n{F}_{7/2}$ displays a thee-peak Zeeman pattern, while $n{F}_{5/2}$ shows a two-peak pattern. Our theoretical models explain all observed spectral characteristics, showing good agreement with the experiment. Our measurements provide a pathway for the study of high-angular-momentum Rydberg states, initialization and coherent manipulation of such states, Rydberg-atom macrodimers, and other Rydberg-atom interactions. Furthermore, the presented methods are suitable for calibration of microwave radiation as well as for nulling and calibration of dc magnetic fields in experimental chambers for cold atoms.

Kashif Ammar Yasir, Wu-Ming Liu

Yuxiang Wang, Qianyi Zhang, Yuqing Liu +3 more

Rydberg atoms play a pivotal role in the fields of quantum simulation, quantum computing, and quantum sensing, in which the frequency locking and detuning of the laser used to excite the atoms to Rydberg states are crucial. Here, we introduce a novel frequency locking approach for Rydberg lasers at arbitrary frequencies using the Zeeman effect of both DC and AC magnetic fields. The DC magnetic field is used to shift the atomic energy levels, thus altering the frequency locking point, while the AC magnetic field is employed for Zeeman modulation to generate the error signal. This method also enables free tuning of the laser frequency within a sub-hundred MHz range by adjusting the DC magnetic field while maintaining frequency locking.

André Deprit, Victor Lanchares, Manuel Iñarrea +2 more

In the classical model for Rydberg atoms, the transition from a pure Zeeman effect to a pure Stark effect passes through a teardrop bifurcation when the magnetic quantum number is not zero. \textcopyright{} 1996 The American Physical Society.

HERBERT WALTHER