A new research achievement demonstrates a significant breakthrough in the field of quantum sensing. The research team successfully developed a novel distributed quantum sensing protocol that can achieve high-precision estimation of global parameters while protecting local data privacy. The team, led by Professor A. de Oliveira Junior from the Technical University of Denmark and Professor Anton L. Andersen from Sorbonne University, advanced this cutting-edge technology using an interconnected network of quantum sensors.
The research indicates that in quantum sensing, it is a major challenge to protect sensitive data when multiple spatially separated sensors collaborate to estimate a common unknown parameter through quantum resources. This study first proposes a theoretical framework that quantifies the trade-off between sensing precision and privacy, revealing the fundamental limits of information leakage. The researchers found that any distributed sensing protocol inevitably leaks a certain amount of information, and the amount of leaked information is linearly related to the number of participants.
To address this issue, the research team proposed a privacy-preserving protocol based on differential privacy. By adding calibrated noise to individual measurement results, they masked the contributions of individual participants while maintaining accurate parameter estimates. This protocol exhibited excellent performance in analysis and numerical evaluation, achieving high-precision sensing while minimizing information leakage, surpassing existing solutions.
Additionally, the research delved into how to achieve global parameter estimation in distributed quantum sensing networks while maintaining the integrity of local encoded values. The results showed that networks using dual-mode squeezed states can simultaneously achieve accurate global estimates and privacy protection for individual components, although complete privacy remains elusive under limited squeezing conditions. By analyzing the effects of practical defects and resource enhancement, the researchers found that while displacement improved estimation precision, it could also affect the level of privacy, whereas optical loss would reduce sensitivity but may not necessarily impact privacy.
This research provides essential tools for the security assessment of quantum parameter estimation and quantum communication protocols, with broad application prospects in fields such as quantum machine learning and quantum sensing. The research team hopes to further explore how to identify the optimal quantum states for constrained sensing tasks in the future, thereby revealing new resources and achieving a better balance between precision and information leakage.
