Robust, Trapped Ultracold Atom Interferometry For Six-axis Inertial Sensing

Sensors based on quantum technology have the potential to transform a number of scientific fields, including environmental sensing, geophysics, and ecology; biology and neuroscience; gravitational wave detection; and air, land, space, and sea-based navigation. One of the key players in quantum inertial sensing, that is, the sensing of acceleration and rotation, is that of atom-based sensing, which makes use of the fact that atoms, like light, can interfere with themselves. Just like one can use conventional matter-based optics to control light waves, one can use light-based optics to control these so-called matter waves, using the light fields generated by lasers to split, reflect, and recombine clouds of atoms. The advantage with these atomic systems is that atom-based rotation sensors can be up to ten billion times more sensitive than their light-based counterparts. The challenge now, for scientists, is to develop robust, scalable quantum sensors that are able to use as much of the massive potential sensitivity advantage as possible while being easily deployable in real-world scenarios.

In this project, we are using shaken lattice interferometry (SLI), where ultracold atoms are trapped in a three-dimensional optical lattice. This optical lattice is the egg-carton-like potential produced when six lasers interfere with one another, two from each of the three dimensions. When the lattice potential is phase modulated (i.e., shaken), the trapped atoms, acting as matter waves, are made to split apart, move in a predetermined way, then come back together, after which an acceleration or rotation signal can be measured.

While SLI is less mature than other atom interferometry techniques, it has the advantage that the atoms remain trapped throughout the interferometry sequence. In addition, the matter-wave optics of the shaken lattice interferometer can be modified to change the sensitivity of the interferometer to signals of differing magnitude and frequency. Additionally, SLI is easily scalable to a six-axis inertial sensor capable of measuring rotation and acceleration along all three dimensions.

The goal of this work is to bring SLI to maturity. That is, in close collaboration with our industry partners, ColdQuanta, Inc, we will demonstrate a robust six-axis inertial sensor based on the concept of SLI with scaling and sensitivity on par with or better than the current state-of-the-art. In addition, we will work to understand the fundamental limits of this relatively new technology, as well as whether or not it can achieve sensitivity scaling and robustness that is better than any previous device. This will lay the foundation for the development of a practical, deployable, and scalable atom-based quantum inertial sensor that has the potential to revolutionise the field of navigation.