Jones Jonathan A, Karlen Steven D, Fitzsimons Joseph, Ardavan Arzhang, Benjamin Simon C, Briggs G Andrew D, Morton John J L
Centre for Advanced Electron Spin Resonance (CAESR), Clarendon Laboratory, Oxford University, Oxford OX1 3PU, UK.
Science. 2009 May 29;324(5931):1166-8. doi: 10.1126/science.1170730. Epub 2009 Apr 23.
Quantum entangled states can be very delicate and easily perturbed by their external environment. This sensitivity can be harnessed in measurement technology to create a quantum sensor with a capability of outperforming conventional devices at a fundamental level. We compared the magnetic field sensitivity of a classical (unentangled) system with that of a 10-qubit entangled state, realized by nuclei in a highly symmetric molecule. We observed a 9.4-fold quantum enhancement in the sensitivity to an applied field for the entangled system and show that this spin-based approach can scale favorably as compared with approaches in which qubit loss is prevalent. This result demonstrates a method for practical quantum field sensing technology.
量子纠缠态可能非常脆弱，很容易受到外部环境的干扰。这种敏感性可用于测量技术，以创建一种在基本层面上性能优于传统设备的量子传感器。我们将一个经典（非纠缠）系统的磁场灵敏度与一个由高度对称分子中的原子核实现的10量子比特纠缠态的磁场灵敏度进行了比较。我们观察到，对于纠缠系统，其对外加磁场的灵敏度有9.4倍的量子增强，并且表明与普遍存在量子比特损失的方法相比，这种基于自旋的方法可以很好地扩展。这一结果展示了一种实用量子场传感技术的方法。
