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Updated: Jun 26, 2026

Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps
Published on: August 17, 2017
Combination of BLOCH oscillations with a Ramsey-Bordé interferometer: new determination of the fine structure
Malo Cadoret1, Estefania de Mirandes, Pierre Cladé
1Laboratoire Kastler Brossel, Ecole Normale Supérieure, Université Pierre et Marie Curie, CNRS, 4 place Jussieu, 75252 Paris Cedex 05, France.
Abstract:
We report a new experimental scheme which combines atom interferometry with Bloch oscillations to provide a new measurement of the ratio h/mRb. 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/mRb leads to a new determination of the fine structure constant alpha(-1) =137.03599945 (62) with a relative uncertainty of 4.6 x 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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