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arXiv · 0812.3139

Determination of the fine structure constant with atom interferometry and Bloch oscillations

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

We use Bloch oscillations to transfer coherently many photon momenta to atoms. Then we can measure accurately the recoil velocity $\hbar k/m$ and deduce the fine structure constant $α$. The velocity variation due to Bloch oscillations is measured using atom interferometry. This method yields to a value of the fine structure constant $α^{-1}= 137.035 999 45 (62)$ with a relative uncertainty of about $4.5 \times 10^{-9}$.

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Malo Cadoret, Estefania De Mirandes, Pierre Cladé, Catherine Schwob, François Nez, Lucile Julien, François Biraben, Saïda Guellati-Khélifa. 2008-12-16. Determination of the fine structure constant with atom interferometry and Bloch oscillations. https://doi.org/10.1142/9789814273008_0007

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