Faraday rotation in the presence of deep repulsive traps

B. Dubetsky, P. R. Berman

Petr M. Anisimov, Ахмеджанов Ринат Абдулхаевич, I. V. Zelensky +1 more

The nonlinear resonance Faraday effect is studied under the condition of coherent population trapping in 87 Rb vapor at the D 1 -line F =2→ F ′=1 transition. The influence of transverse magnetic fields on the nonlinear optical Faraday rotation is studied. For the transverse fields perpendicular to the electromagnetic-wave polarization, a simple theoretical model is proposed, which is in good agreement with experimental data. The optimal intensity providing the maximum sensitivity is found based on the results obtained. The influence of working-level depletion on the parameters of Faraday rotation in open systems is studied experimentally and theoretically. The system was closed in the experiment by using an additional laser to increase the sensitivity and extend the dynamic range of measured fields. The importance of compensating for the depletion in the presence of spurious magnetic fields is shown; in particular, the sensitivity was enhanced by a factor of 50 in experiments with a buffer gas.

H. M. Gibbs, G. G. Churchill, G. J. Salamo

Akira Terasaki, T. Majima, Tamotsu Kondow

A novel experimental method is presented for detection of a trace of optical absorption of mass-selected ions stored in an ion trap. Photon-trap spectroscopy (a generalized scheme of cavity ring-down spectroscopy) is the key technique, where a storage lifetime of photons in a high-Q cavity provides a ppm-level high sensitivity. Experiment was performed on the manganese ion, Mn + , to record 7 P 2,3,4 ← 7 S 3 absorption spectra at around 260 nm. Zeeman splitting and Faraday rotation of the polarization plane were observed as well in the presence of a magnetic field. The high-resolution spectra show complex structures, which are fully interpreted by the quantum theory incorporating hyperfine interaction due to the Mn nuclear spin ( I = 5/2). The present technique provides a novel approach to electronic and magnetic structures of mass-selected atomic, molecular, and cluster ions.

Adam M. Wojciechowski, Eric Corsini, Jerzy Zachorowski +1 more

We report on the first observation of Nonlinear Faraday Rotation (NFR) with cold atoms prepared in a magneto-optical trap (MOT) at ∼100µK temperature. The nonlinearity of rotation results from long-lived coherence of ground-state Zeeman sublevels [1], which makes NFR a candidate for the study and sensitive detection of qubits.

А. А. Папченко, Evgenii A. Yukov