Accurate rotation rate measurements with a cold atom interferometer

Romain Gautier, Leonid A. Sidorenkov, Matteo Altorio +2 more

Ken Takase

Xiong Zong-Yuan, Yao Zhanwei, Ling Wang +3 more

Cold atoms possess low velocity, narrow velocity distribution as well as good matter wave coherence, thus they have been used to achieve cold atom interferometers. The interferometers with Sagnac effect form atom gyroscopes which can measure rotation rate accurately. Here we report our recent progress in building a projectile cold atom gyroscope. We achieve the accurate control of the bidirectional projectile cold atom motion through the use of a homemade direct digital frequency synthesizer.

Christopher Jekeli

The recent development of the atom interferometer and its demonstration as an inertial sensor of acceleration and rotation rate augur a new generation of inertial navigation systems that would rival today's satellite navigation accuracy at the few-meter level. This paper reviews the principles of inertial measurement using the atom interferometer from a rudimentary viewpoint to illustrate the fundamentals and to highlight some of the potential shortcomings with a particular type, the cold-atom interferometer. One of these shortcomings is the fact that this interferometer requires a finite period of time during which the atoms are prepared (cooled) before they enter the interferometer and respond to its dynamics relative to an inertial frame. This lapse in the measurement duty cycle could be supplemented with very precise conventional inertial measurement units (IMUs), or eliminated with multiple, interleaved atom interferometers. Error analyses show that cold-atom interferometric IMUs that capture 50 percent of the dynamics must be coupled with conventional IMUs that are 50 times more accurate than typical navigation-grade units to sustain a horizontal position error of under 5 m (root mean square) after 1 h.

Carlos L. Garrido Alzar

This work reviews the topic of rotation sensing with compact cold atom interferometers. A representative set of compact free-falling cold atom gyroscopes is considered because, in different respects, they establish a rotation-measurement reference for cold guided-atom technologies. This review first discusses enabling technologies relevant to a set of key functional building blocks of an atom chip-based compact inertial sensor with cold guided atoms. These functionalities concern the accurate and reproducible positioning of atoms to initiate a measurement cycle, the coherent momentum transfer to the atom wave packets, the suppression of propagation-induced decoherence due to potential roughness, on-chip detection, and vacuum dynamics because of its impact on sensor stability, which is due to the measurement dead time. Based on the existing enabling technologies, the design of an atom chip gyroscope with guided atoms is formalized using a design case that treats design elements such as guiding, fabrication, scale factor, rotation-rate sensitivity, spectral response, important noise sources, and sensor stability.

Romain Gautier, Matteo Altorio, Leonid A. Sidorenkov +2 more