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arXiv · 1306.4368

High-Precision Spectroscopy with Counter-Propagating Femtosecond Pulses

Itan Barmes·Stefan Witte·Kjeld S. E. Eikema
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Abstract

An experimental realization of high-precision direct frequency comb spectroscopy using counter-propagating femtosecond pulses on two-photon atomic transitions is presented. Doppler broadened background signal, hampering precision spectroscopy with ultrashort pulses, is effectively eliminated with a simple pulse shaping method. As a result, all four 5S-7S two-photon transitions in a rubidium vapor are determined with both statistical and systematic uncertainties below 10$^{-11}$, which is an order of magnitude better than previous experiments on these transitions.

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Itan Barmes, Stefan Witte, Kjeld S. E. Eikema. 2013-06-18. High-Precision Spectroscopy with Counter-Propagating Femtosecond Pulses. https://doi.org/10.1103/physrevlett.111.023007

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