Improving cold-atom sensors with quantum entanglement: Prospects and challenges

Quantum entanglement has been generated and verified in cold-atom experiments and used to make atom-interferometric measurements below the shot-noise limit. However, current state-of-the-art cold-atom devices exploit separable (i.e., unentangled) atomic states. This perspective piece asks the question: can entanglement usefully improve cold-atom sensors, in the sense that it gives new sensing capabilities unachievable with current state-of-the-art devices? We briefly review the state-of-the-art in precision cold-atom sensing, focusing on clocks and inertial sensors, identifying the potential benefits entanglement could bring to these devices, and the challenges that need to be overcome to realize these benefits. We survey demonstrated methods of generating metrologically useful entanglement in cold-atom systems, note their relative strengths and weaknesses, and assess their prospects for near-to-medium term quantum-enhanced cold-atom sensing.

Automated summary

This perspective piece explores the potential benefits of utilizing quantum entanglement to improve cold-atom sensors beyond what current state-of-the-art devices can achieve. The review focuses on the state-of-the-art in precision cold-atom sensing, discussing the benefits entanglement could bring and the challenges that need to be addressed to realize these improvements. Demonstrated methods of generating metrologically useful entanglement in cold-atom systems are surveyed, with an assessment of their prospects for enhancing cold-atom sensing in the near-to-medium term.