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arXiv · 0810.3152

Combination of Bloch oscillations with a Ramsey-Bordé interferometer : new determination of the fine structure constant

Malo Cadoret·Estefania De Mirandes·Pierre Cladé·Saïda Guellati-Khélifa·Catherine Schwob·François Nez·Lucile Julien·François Biraben
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Abstract

We report a new experimental scheme which combines atom interferometry with Bloch oscillations to provide a new measurement of the ratio $h/m_{\mathrm{Rb}}$. By using Bloch oscillations, we impart to the atoms up to 1600 recoil momenta and thus we improve the accuracy on the recoil velocity measurement. The deduced value of $h/m_{\mathrm{Rb}}$ leads to a new determination of the fine structure constant $α^{-1}=137.035 999 45 (62)$ with a relative uncertainty of $4.6\times 10^{-9}$. The comparison of this result with the value deduced from the measurement of the electron anomaly provides the most stringent test of QED.

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Malo Cadoret, Estefania De Mirandes, Pierre Cladé, Saïda Guellati-Khélifa, Catherine Schwob, François Nez, Lucile Julien, François Biraben. 2008-10-17. Combination of Bloch oscillations with a Ramsey-Bordé interferometer : new determination of the fine structure constant. https://doi.org/10.1103/physrevlett.101.230801

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