Measuring the Newtonian constant of gravitation G with an atomic interferometer

We have recently completed a measurement of the Newtonian constant of gravitation G using atomic interferometry. Our result is G=6.67191(77)(62)×10−11 m3 kg−1 s−2 where the numbers in parenthesis are the type A and type B standard uncertainties, respectively. An evaluation of the measurement uncertainty is presented and the perspectives for improvement are discussed. Our result is approaching the precision of experiments based on macroscopic sensing masses showing that the next generation of atomic gradiometers could reach a total relative uncertainty in the 10 parts per million range.