Quantum Sensors Advance Precision Measurement, Scaling with Loss of Particles
Scientists have made a breakthrough in quantum sensing, developing a unified theory that allows for highly precise measurements—even when particles are lost. The research introduces a new framework that improves sensor performance under realistic conditions, overcoming previous limitations in quantum technology.
Teams from the University of Bonn and the Technical University of Dresden contributed key innovations, including portable designs for medical applications like epilepsy research.
The new theory integrates techniques from Ramsey, twist-untwist, and random sensing using operator algebra. Researchers discovered that the way quantum states are prepared directly affects a sensor’s sensitivity. By analysing the orbits created during state preparation and sensing, they engineered systems that achieve far greater precision than standard methods.
A major finding involves the Quantum Fisher Information (QFI) matrix. The study shows that the ratio of its diagonal to off-diagonal elements grows with the number of subsystems, explaining why these sensors perform better. This insight helps predict and enhance performance even when noise or particle loss occurs. The team also introduced a resilient sensor design based on projected ensembles. This approach partitions a quantum system into unevenly sized subsystems, maintaining high accuracy despite imperfections. Careful tuning of the projection process further reduces errors, allowing measurements to reach the highest possible precision. Additionally, the research links quantum symmetries to sensor precision. By controlling the interaction between specific Hamiltonians, scientists can scale Fisher information—an essential factor in measurement accuracy. Dynamical Lie Algebras (DLAs) provided the mathematical foundation for this unified approach, enabling the analysis and improvement of diverse quantum sensors. Practical applications are already emerging. Simon Ebbinghaus and Puja Shrestha at the University of Bonn developed sensors for moving brains, aiding epilepsy research. Meanwhile, Dr.-Ing. Martha Kalina at Dresden patented portable quantum sensors with high-precision falling designs, expanding real-world uses.
The unified framework allows quantum sensors to operate at peak performance even with noise or particle loss. This advancement removes key barriers in quantum measurement, opening doors for medical, industrial, and scientific applications. Portable, high-precision sensors are now closer to widespread use in fields like neurology and beyond.
