New quantum devices based on manipulations of Bose-Einstein condensate (BEC) on microfabricated chips hold great promise for application to high precision inertial navigation. By employing appropriate mechanizations which separate acceleration and rotation sensitivities, atom interferometers can have dual functionality as both accelerometers and gyroscopes. BEC interferometers could offer ten orders of magnitude inertial measurement improvement with possibility of developing highly sensitive inertial measurement unit (IMU) which would provide extremely accurate free-inertial navigation with long-term accuracy. This is very suitable for applications in undersea environments where direct use of the Global Positioning System (GPS) is denied. Due to the high sensitivity of BEC and the complexity of microfabricated structures, application specific sources of decoherence, environmental noises, and errors are modeled and studied.
New quantum devices based on manipulations of Bose-Einstein condensate (BEC) on microfabricated chips hold great promise for application to high precision inertial navigation. By employing appropriate mechanizations which separate acceleration and rotation sensitivities, atom interferometers can have dual functionality as both accelerometers and gyroscopes. BEC interferometers could offer ten orders of magnitude inertial measurement improvement with possibility of developing highly sensitive inertial measurement unit (IMU) which would provide extremely accurate free-inertial navigation with long-term accuracy. This is very suitable for applications in undersea environments where direct use of the Global Positioning System (GPS) is denied. Due to the high sensitivity of BEC and the complexity of microfabricated structures, application specific sources of decoherence, environmental noises, and errors are modeled and studied.
Quantum technology became a new tool for navigation based on measuring accelerations and rotations. However, the full potential of atom interferometers that operate with ultracold atoms has not yet been exploited. This paper presents current developments in the field of generation and application of Bose–Einstein condensates for inertial navigation. It covers the advancements in the form of atom chip and compact vacuum technology, classical sensor hybridization, and a multi-axis atom interferometry technique. In addition, the synergies of combining quantum sensors with classical inertial measurement units and their implications for navigation trajectories are discussed.
Matter-wave interferometers show great a potential for improving inertial sensing. The absence of drifts recommends them for a variety of applications in geodesy, navigation, or fundamental physics. Here, ultracold atomic ensembles, featuring a velocity distribution well below the photon recoil velocity, open up new perspectives. In contrast to standard laser cooling methods, they allow to reach better beam-splitting efficiencies and, hence, a higher contrast as well as to reduce systematic uncertainties and biases. Presently, Bose-Einstein condensates (BECs) provide the means to achieve the lowest expansion energies of few picokelvin. Indeed, the momentum distribution of a BEC can be further narrowed after reaching the regime of ballistic expansion, where all mean field energy is converted to kinetic energy, by the application of the delta-kick collimation technique. With such ensembles, Bragg processes can be driven with an efficiency of above 95% as well as Bloch oscillations performed without large atomic losses or dephasing. Both enable efficient large momentum transfer in interferometers to enhance their sensitivity for inertial effects. In a so-called twin-lattice atom interferometers more than thousand photon recoils are used to form compact but sensitive atom interferometers. These methods not only bring in reach extremely accurate gravimeters and accelerometers but also gyroscopes. Like the Sagnac effect in ring laser or fiber gyroscopes, the sensitivity of atom interferometers to rotations increases with the space-time area enclosed by the interferometer. In the case of light interferometers, the latter can be enlarged by forming multiple fiber loops. However, the equivalent for matter-wave interferometers remains an experimental challenge. An atom interferometer with scalable area may be formed in a twin lattice combined with a relaunch mechanism to obtain multi loops as well. Due to this scalability, it offers the perspective of reaching unprecedented sensitivities for rotations in comparably compact sensor head setups. Moreover, atom-chip technologies offer the possibility to generate a BEC and perform delta-kick collimation in a fast and reliable away, paving the way for field-deployable miniaturized atomic devices. Last but not least, the extremely low expansion energies of BECs open up to extend the time atoms spend in the interferometer to tens of seconds. This brings in reach unprecedented sensitivities in space-borne applications such as satellite geodesy.
The growing reliance on Global Positioning System (GPS) technologies across critical sectors such as defense, aerospace, and autonomous systems highlights the need for navigation solutions that are robust against signal loss, spoofing, and jamming. Quantum-based navigation systems offer a promising alternative, leveraging the fundamental principles of quantum mechanics to achieve unprecedented precision and resilience. This paper provides an overview of the core quantum technologies enabling this next generation of navigation, including atomic interferometry, quantum accelerometers, gyroscopes, and ultra-precise quantum clocks. Cold atom techniques and laser cooling play pivotal roles in enhancing measurement stability and accuracy. The integration of these technologies into inertial navigation systems (INS) significantly reduces drift and extends operational reliability in GPS-denied environments. Quantum navigation technologies are finding applications across a wide range of domains, including military defense, underwater missions, space travel, and autonomous transportation. Despite existing obstacles such as high development costs, environmental sensitivity, and the need for further miniaturization, progress in quantum sensor development and engineering continues at a steady pace. This article presents an overview of the fundamental concepts, present capabilities, and prospective advancements in quantum navigation. It also highlights the technology's promise as a viable alternative or even a possible replacement for conventional GPS systems.
We are developing an atom interferometer that measures horizontal accelerations to form a component of a quantum inertial measurement unit. Benefitting from the inherent stability of atom interferometry, this points to a navigation system that offers long-term accuracy without recourse to GPS. To aid compactness and transportability, the sub-components of the quantum sensor are mounted in a 19-inch rack. This includes an optical system of two titanium-sapphire lasers that delivers all of the optical pulses required to operate a highly sensitive atom interferometer using 87Rb atoms. Active compensation systems that allow operation of the quantum sensor in the noisy environment of a moving vehicle are described. Finally, we give an account of recent field trials on a variety of test platforms.
Recent technological advancements in atom interferometry have demonstrated extremely precise inertial measurements of acceleration and rotation. These could be used to develop ultra-precise inertial navigation systems that approach GPS navigation. The paper presents a rudimentary exposition of the interferometer which is based on beams of atoms cooled by lasers to a velocity of the order of 1 m/s and launched along two trajectories that re-combine, as in a classical interferometer. Using the dual wave-particle quantum mechanical properties of atoms, the differential phase of the interfering beams is indicative of inertial acceleration and rotation, similar to the Sagnac effect. Due to the much shorter wavelength of the atomic beam, the sensitivity is many orders of magnitude greater. Concluding analyses show that an inertial navigation system with 5/hr drift is technically possible.
Atomic quantum sensors are a major breakthrough in the technology of time and frequency standards as well as ultra-precise sensing and monitoring of accelerations and rotations. They apply a new kind of optics based on matter waves. Today, atomic clocks are the standard for time and frequency measurement at the highest precisions. Inertial and rotational sensors using atom interferometers have already shown similar potential for replacing state-of-the-art sensors in other fields. With Bose-Einstein condensates, also refered as atom lasers, the traditional experiments with atom interferometers can be greatly improved. Testing of fundamental principles, studies of atomic properties, applications as inertial sensors, and measurements of fundamental constants can benefit from the brightness (intensity and small momentum spread) of these coherent sources. In addition, the coherence properties of condensates may also allow BEC based atom interferometers to approach the Heisenberg detection limit. This corresponds to a measurement precision which scales like 1/N for N atoms and not like 1 / N as for independent measurements on N atoms.