High-accuracy inertial measurements with cold-atom sensors

Abstract

The research on cold-atom interferometers gathers a large community of about 50 groups worldwide both in the academic and now in the industrial sectors. The interest in this sub-field of quantum sensing and metrology lies in the large panel of possible applications of cold-atom sensors for measuring inertial and gravitational signals with a high level of stability and accuracy. This review presents the evolution of the field over the last 30 years and focuses on the acceleration of the research effort in the last 10 years. The article describes the physics principle of cold-atom gravito-inertial sensors as well as the main parts of hardware and the expertise required when starting the design of such sensors. It then reviews the progress in the development of instruments measuring gravitational and inertial signals, with a highlight on the limitations to the performances of the sensors, on their applications, and on the latest directions of research.

Quantum time dilation in atomic spectra

“…The effects of quantum time dilation on atomic spectra complement the growing literature on relativistic clock interferometry, which also probes the effects of suppositions of clocks experiencing different proper times due to both special or general relativistic effects [16,18,[31][32][33][34]67]. In contrast, we propose a spectroscopic signature of proper time superpositions that can probe quantum theory and relativity in the regime in which coherence across relativistic momentum wave packets plays a role.…”

“…Experimental considerations -Since the initial prediction of wave-particle duality by de Broglie, atomic interferometry has witnessed tremendous conceptual and technological progress [57]. With the advent of large momentum beamsplitters [58][59][60][61][62], atomic beams travelling along distinct trajectories have been realized, providing a quantum based alternative to classical gravimeters, gradiometers and accelerometers [34,[63][64][65][66][67]. In these settings, the usual strategy is to suppress radiation losses as they inflict disruptions in phase relations between interferometer's arms [62].…”

Inertial sensing with quantum gases: a comparative performance study of condensed versus thermal sources for atom interferometry

“…Experiments based on the interference of freely falling atoms measure accelerations [13,1], rotations [14,15,16,17,18], gravity gradients [19,20], determine fundamental constants [2,21,22], perform tests of fundamental physics [23,2,22,24,25,26,3,27], and are proposed for the detection of gravitational waves [28,29,4,30,31]. A recent review of the advances in the field of inertial sensing collects most relevant experiments and proposals so far [1]. Beyond proofof-principle demonstrations, ongoing developments target commercialisation as well as challenge the state of the art in sensor performance and in fundamental science.…”

“…Atom interferometers are mainly used for inertially sensitive measurements [1] and a variety of tests of fundamental physics [2,3]. Key levers to increase the sensitivity are the transfer of a large number of photons during the beamsplitting processes, extending the time of free fall while maintaining contrast and atomic flux.…”

Tailoring multi-loop atom interferometers with adjustable momentum transfer

“…Matter-wave interference is a central concept of quantum mechanics with a myriad of applications making use of electrons [1], neutrons [2], or atoms and molecules [3]. Examples of applications range from bacteria characterization [4] and biomolecular analysis [5], to fundamental physics tests [6] and accurate inertial sensing [7]. In most cases, a required high degree of control over the interference conditions and the precision of a measurement rely on the interference of two waves, with a sinusoidal fringe pattern providing direct access to the phase shift.…”