Simultaneous measurement of gravity acceleration and gravity gradient with an atom interferometer

Abstract

We demonstrate a method to measure the gravitational acceleration with a dual cloud atom interferometer; the use of simultaneous atom interferometers reduces the effect of seismic noise on the gravity measurement. At the same time, the apparatus is capable of accurate measurements of the vertical gravity gradient. The ability to determine the gravity acceleration and gravity gradient simultaneously and with the same instrument opens interesting perspectives in geophysical applications.

Advances in precision contrast interferometry with Yb Bose-Einstein condensates

“…Therefore, the phase is greatest in the center of a branch and decreases into the wings. This effect scales like (∆t) 2 , where ∆t is the difference in time between the proper closing time and the time when data is taken. This shift can be made negligibly small by taking data at ∆t = 0 rather than at 2T .…”

“…These same effects can be harnessed in a matter-wave interferometer for precision measurements [1]. Matter-wave interferometers have been used for a variety of precision measurements, from applications such as measuring gravity and gravity gradients [2] or rotation sensing [3] to fundamental physics such as measuring the fine structure constant [4] or atomic polarizabilities [5]. Most precision measurements rely on incoherent sources of atoms such as beam lines or laser-cooled clouds.…”

Measuring the Tidal Force on a Particle’s Matter Wave

“…Our approach differs from that employed by previous precision atomic gravity gradiometers [11][12][13], which used independently generated atom clouds separated by a baseline as the sources for two accelerometers. These gradiometers were subject to uncertainty in the baseline length due to source position fluctuations.…”

Inertial quantum sensors using light and matter

“…This is the case with both atomic clocks, where the quality of the local oscillator used to interrogate the atomic coherence ultimately limits the measurement, and with accelerometers and gyroscopes based on matter-wave interference, where the fringe visibility is degraded by acceleration and rotation noise, respectively. Several solutions to extend the interrogation interval have been proposed for atomic clocks [78,79] and demonstrated in atom interferometry based inertial sensing [80]; they use two or more ensembles interrogated simultaneously at different time scales or locations to increase the phasewrap-free interval. With our system, we can measure the population imbalance in an atom interferometer with a minimal destructivity of the ensemble coherence.…”