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arXiv · 0809.3167

Precise determination of h/m_Rb using Bloch oscillations and atomic interferometry: a mean to deduce 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 use Bloch oscillations to transfer coherently many photon momenta to atoms. Then we can measure accurately the ratio h/m_Rb and deduce the fine structure constant alpha. The velocity variation due to the Bloch oscillations is measured thanks to Raman transitions. In a first experiment, two Raman $π$ pulses are used to select and measure a very narrow velocity class. This method yields to a value of the fine structure constant alpha^{-1}= 137.035 998 84 (91) with a relative uncertainty of about 6.6 ppb. More recently we use an atomic interferometer consisting in two pairs of pi/2 pulses. We present here the first results obtained with this method.

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Malo Cadoret, Estefania De Mirandes, Pierre Cladé, Saïda Guellati-Khélifa, Catherine Schwob, François Nez, Lucile Julien, François Biraben. 2008-09-18. Precise determination of h/m_Rb using Bloch oscillations and atomic interferometry: a mean to deduce the fine structure constant. https://doi.org/10.1140/epjst%2Fe2008-00813-9

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