Study of dynamics of Rabi oscillation under a pulsed perturbation using hyperfine transition of trapped cesium atoms

We study dynamics of Rabi oscillation under a periodic pulsed perturbation. We study how the resonance frequency of a cesium ground hyperfine transition between sublevels with nonzero magnetic quantum number is affected by periodically applied magnetic pulses. When the pulse height and pulse duration are set such that a fictitious spin completes a 2$\pi $ or its integer multiple precession around the principal quantization axis, there is no frequency shift [1]. We carry out the experiment using spin-polarized cesium atoms trapped in a magneto-optical trap. This has an important implication for metrological application of atoms trapped in an optical trap, where a systematic frequency shift and inhomogeneous broadening due to an ac Stark shift limits accuracy and precision. Our method is complimentary to the ones using a magic wavelength in a multi-level configuration [2-4] or a polarization dependence of the ac Stark shift to compensate for the differential ac Stark shift [5]. \newline [1] J M Choi, G N Kim, C. I. Sukenik and D. Cho, J. Korea Phys. Soc. submitted (2007)\, [2] Ji Yeon Kim and D. Cho, J. Korean Phys. Soc. \textbf{37}, 744 (2000)\, [3] D. Cho \textit{et al}, J. Korean Phys. Soc. \textbf{42}, 483 (2003)\, [4] Mckeer J, Boca A, Brooze A D and Kimble H J, Nature \textbf{425}, 268 (2003) [5] J M Choi and D. Cho, \textit{Proc. Int. Conf. in India}, submitted (2007)