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arXiv · 1411.3849

Femtosecond wavepacket interferometry using the rotational dynamics of a trapped cold molecular ion

J. Martin Berglund·Michael Drewsen·Christiane P. Koch
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Abstract

A Ramsey-type interferometer is suggested, employing a cold trapped ion and two time-delayed off-resonant femtosecond laser pulses. The laser light couples to the molecular polarization anisotropy, inducing rotational wavepacket dynamics. An interferogram is obtained from the delay dependent populations of the final field-free rotational states. Current experimental capabilities for cooling and preparation of the initial state are found to yield an interferogram visibility of more than 80\%. The interferograms can be used to determine the polarizability anisotropy with an accuracy of about $\pm 2\%$, respectively $\pm 5\%$, provided the uncertainty in the initial populations and measurement errors are confined to within the same limits.

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J. Martin Berglund, Michael Drewsen, Christiane P. Koch. 2014-11-14. Femtosecond wavepacket interferometry using the rotational dynamics of a trapped cold molecular ion. https://doi.org/10.1088/1367-2630%2F17%2F2%2F025007

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