Measurement of the Earth's Gravity Gradient with an Atom Interferometer-Based Gravity Gradiometer

Abstract

We report the demonstration of an atom interferometer-based gravity gradiometer. The gradiometer uses stimulated two-photon Raman transitions to measure the relative accelerations of two ensembles of laser cooled atoms. We have used this instrument to measure the gradient of the Earth's gravitational field. [S0031-9007(98)06679-4]

Gravitational Perturbations on Local Experiments in a Satellite: The Dragging of Inertial Frame in the HYPER Project

“…In Ψ, the Lense-Thirring term arises from 2K (0)(k) v (k) g ; it is of order of 2 J r 3 Xv g ∼ 1500 ηεO 6 . If the expansion of K (0)(0) is limited to order ε 2 O 6 , the accuracy is of order ε 1500η ∼ 13% with v g ≃ 20 cm · s −1 .…”

“…We consider the case where the experimental set up is built out of several atomic interferometers similar to those which are currently developed in Hannover [2] and [3], Paris [4] and Orsay [5] and [6] (see section V).…”

Noise-Immune Conjugate Large-Area Atom Interferometers

“…Cancellation of vibrations has been demonstrated by using the same laser light to simultaneously address two similar interferometers at separate locations [12][13][14]. This method, however, is restricted to situations where the differential signal is small (in this case, the gravity gradient), so that the interferometers are similar enough to be addressable by the same laser.…”

“…The common phase moves the data points around the ellipse, but the differential phase can be extracted by ellipse-specific fitting. One way that has been realized, without LMT [12][13][14], is to use the same radiation to address both interferometers, which trivially leads to δφ L = 0. However, the use of this method is restricted to measurements of very small differential signals, so that the interferometers are similar; whereas our SCIs are dissimilar and can be sensitive to the relatively large 16n 2 ω r T differential signal.…”

Atom interferometers and optical atomic clocks: New quantum sensors for fundamental physics experiments in space

“…In particular, atom interferometers are new tools for experimental gravitation as, for example, for precision measurement of gravity acceleration [15], gravity gradients [16], Newtonian gravitational constant G [17], gravity at micrometric distances [18,19], and for testing equivalence principle [20]. The possibility of detecting gravitational waves by atom interferometry was also discussed [21,22].…”