Quantum sensors for enhanced positioning and navigation: a comprehensive review

Abstract The inherent vulnerability of Global Navigation Satellite Systems (GNSS) to interference, spoofing, and signal degradation highlights the urgent need for robust augmentation and alternative solutions to support resilient Positioning, Navigation, and Timing (PNT) services. Among emerging technologies, quantum sensing stands out for its ability to harness fundamental quantum phenomena, such as superposition and entanglement, enabling absolute, drift-free and ultra-sensitive measurements of inertial forces, gravity, and magnetic fields with long-term stability and reduced dependency on external signals. This capability offers a promising pathway to enhance positioning and navigation performance in GNSS-denied or GNSS-contested environments. Here, we present a comprehensive review of quantum sensing technologies in the context of positioning and navigation, including cold atom interferometry, atomic vapour cell, superconducting quantum interference devices, and room temperature solid-state systems like nitrogen-vacancy centres in diamond, and their potential to support positioning and navigation across a range of operational contexts. Both standalone and hybrid quantum-classical architectures are examined, with case studies illustrating their ability to reduce navigation drift and achieve sub-metre accuracy through quantum-enhanced inertial navigation, gravity-aided positioning, and magnetic field-matching approach. Despite their promise, challenges including decoherence, environmental robustness, miniaturisation, and integration complexity remain significant barriers to practical deployment. Rather than replacing existing classical systems, quantum sensors are best served as complementary solutions within multi-layered PNT frameworks. This review also identifies priorities for advancing field-deployable quantum positioning and navigation solutions, including sensor robustness, miniaturisation, seamless integration, and the development of protocols to quantify quantum performance. Aligned with international quantum initiatives, this work contributes to the vision of secure, interference-resistant navigation infrastructure for scientific, industrial, and defence applications.