Eur. Phys. J. Special Topics 163, 101-111 (2008)
https://doi.org/10.1140/epjst/e2008-00813-9

Precise determination of h/m_Rb using Bloch oscillations and atomic interferometry: A mean to deduce the fine structure constant

¹ Laboratoire Kastler Brossel, ENS, CNRS, UPMC, 4 place Jussieu, 75252 Paris Cedex 05, France
² INM, Conservatoire National des Arts et Métiers, 61 rue Landy, 93210 La plaine Saint-Denis, France

Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

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 α. 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 α^-1= 137.03599884(91) with a relative uncertainty of about 6.6 ppb. More recently we use an atomic interferometer consisting in two pairs of π/2 pulses. We present here the first results obtained with this method.