We present a mobile 3D accelerometer based on matter-wave interferometry, which is capable of measuring three orthogonal accelerations, each with respect to an independent inertial reference frame defined by the surface of a mirror. On each axis, we construct a hybrid quantum/classical accelerometer by using correlations between the atoms and a mechanical accelerometer attached to the back of each reference mirror. This system combines the large bandwidth and dynamic range of classical devices with the high sensitivity and accuracy of atom interferometers. By correcting each classical accelerometer independently, we are able to track the full acceleration vector with high accuracy.
The emergence of quantum technologies, including cold atom based accelerometers, offers an opportunity to improve the performances of space geodesy missions. In this context, CNES initiated an assessment study called GRICE (GRadiométrie à Interféromètres quantiques Corrélés pour l’Espace) in order to evaluate the impact of cold atom technologies to space geodesy and to the end users of the geodetic data. In this paper, we present a specific mission scenario for gravity field mapping based on a twin satellite concept. The mission uses a constellation of two satellites each equipped with a cold atom accelerometer. A laser link measures the distance between the two satellites and couples these two instruments in order to produce a correlated differential acceleration measurement. The main parameters, determining the performances of the payload, have been investigated. In addition, a preliminary study of mass, consumption and volume has been conducted to ensure the onboard feasibility of these instruments. A general study of the satellite architecture, including all the subsystems, has also been realized and is presented here.
Over the past few decades, the development of laser-cooling techniques has made it possible to exploit the quantum properties of matter at very low temperatures. These techniques have enabled experimentalists to coherently manipulate quantum objects with a very high degree of precision. In this context, atom interferometry has emerged as a powerful tool for metrology. Nowadays, atom interferometers (AIs) are used for a wide range of applications, such as sensitive probes of inertial forces, or studies of fundamental physics and tests of gravitational theories. Our experiment uses a dual-species gravimeter to test the weak equivalence principle (WEP). Here, two overlapped samples of 39K and 87Rb are simultaneously interrogated during free-fall—yielding a precise measurement of their differential acceleration under gravity. These experiments have been carried out in the weightless on ground and in the environment of parabolic flight.
The new compact transportable quantum sensors used for drift-free integration in the 0-g airbus.
The starting point for many experiments aimed at studying fundamental physics is to prepare a pure sample in terms of its energy, spin and momentum before injecting into an atom interferometer, spectrometer or quantum simulator. We will present an all-optical technique to prepare ultra-cold sample in magnetically insensitive state with high purity, a versatile preparation scheme particularly well suited to performing matter-wave interferometry with species exhibiting closely separated hyperfine levels, such as the isotopes of lithium and potassium.
We will also present the recent progress in measuring the Eotvos parameter which compared the gravitational acceleration measured by two atomic species. We will finally discuss how precision atom interferometry can be used to perform long-term, drift-free integration even in the harsh environment of the plane, and thus provide a new tool for precision measurement and navigation.
We have developed a Watt-level single-frequency tunable fiber laser in the 915-937 nm spectral window. The laser is based on a neodymium-doped fiber master oscillator power amplifier architecture, with two amplification stages using a 20 mW extended cavity diode laser as seed. The system output power is higher than 2 W from 921 to 933 nm, with a stability better than 1.4% and a low relative intensity noise.
The Space-Time Explorer and Quantum Test of the Equivalence Principle mission (STEQUEST) is devoted to a precise measurement of the effect of gravity on time and matter using an atomic clock and an atom interferometer. The mission was selected by ESA as one of four candidates for the M3 mission within the Cosmic Vision Program (launch in 2022).
During the past decades, atom interferometry experiments were developed for various applications like precision measurement of fundamental constants [1, 2], gravimetry , gradiometry  or inertial sensing [5, 6].
The Matter-Wave laser Interferometer Gravitation Antenna, MIGA, will be a hybrid instrument composed of a network of atom interferometers horizontally aligned and interrogated by the resonant ﬁeld of an optical cavity. This detector will provide measurements of sub Hertz variations of the gravitational strain tensor. MIGA will bring new methods for geophysics for the characterization of spatial and temporal variations of the local gravity ﬁeld and will also be a demonstrator for future low frequency Gravitational Wave (GW) detections. MIGA will enable a better understanding of the coupling at low frequency between these diﬀerent signals. The detector will be installed underground in Rustrel (FR), at the “Laboratoire Souterrain Bas Bruit” (LSBB), a facility with exceptionally low environmental noise and located far away from major sources of anthropogenic disturbances. We give in this paper an overview of the operating mode and status of the instrument before detailing simulations of the gravitational background noise at the MIGA installation site.
Inertial sensors based on cold atom interferometry exhibit many interesting features for applications related to inertial navigation, particularly in terms of sensitivity and long-term stability. However, at present the typical atom interferometer is still very much an experiment—consisting of a bulky, static apparatus with a limited dynamic range and high sensitivity to environmental eﬀects. To be compliant with mobile applications further development is needed. In this work, we present a compact and mobile experiment, which we recently used to achieve the ﬁrst inertial measurements with an atomic accelerometer onboard an aircraft. By integrating classical inertial sensors into our apparatus, we are able to operate the atomic sensor well beyond its standard operating range, corresponding to half of an interference fringe. We report atom-based acceleration measurements along both the horizontal and vertical axes of the aircraft with one-shot sensitivities of 2.3 × 10−4 g over a range of ∼ 0.1 g. The same technology can be used to develop cold-atom gyroscopes, which could surpass the best optical gyroscopes in terms of long-term sensitivity. Our apparatus was also designed to study multi-axis atom interferometry with the goal of realizing a full inertial measurement unit comprised of the three axes of acceleration and rotation. Finally, we present a compact and tunable laser system, which constitutes an essential part of any cold-atom-based sensor. The architecture of the laser is based on phase modulating a single ﬁber-optic laser diode, and can be tuned over a range of 1 GHz in less than 200 μs.
We report improvements to our atom-interferometer based Sagnac gyroscope which uses stimulated Raman transitions to manipulate atomic wavepackets of cesium atoms. Using counter-propagating high-flux atomic beams, we form two interferometers with opposite Sagnac phase shifts that share key components such as Raman atomic state manipulation beams. Subtracting the two interferometer signals allows the common-mode rejection of spurious noise sources and various systematic effects. Preliminary results indicate a short term sensitivity of 3 X 10-9 (rad/s) (root) Hz.