论文标题
远程量子传感在许多身体系统中使用Heisenberg有限的灵敏度
Remote Quantum Sensing with Heisenberg Limited Sensitivity in Many Body Systems
论文作者
论文摘要
就资源效率而言，量子传感器已显示出优于其经典的传感器。这些传感器传统上使用了特殊形式的最初纠缠状态的特殊形式的时间演变，自适应测量基础变化或多体系统的基础状态。在这里，我们提出了一种不同的量子传感方式，该方法利用了以产品状态初始初始化的多体系统的动力学以及在特定基础上进行投影测量的顺序。该过程具有多个实际优势：（i）启用远程量子感应，保护样品免受潜在的侵入性读数设备的影响； （ii）通过避免复杂的纠缠或关键的接地状态来简化初始化。从基本的角度来看，它利用了到目前为止的资源来传感，即，在伴随测量结果的波功能崩溃之后，来自多体系统未观察到的部分的残差信息。通过增加测量序列的数量，通过贝叶斯估计量的均值，超出标准限制的精度，接近海森堡结合，被证明是可以实现的。
Quantum sensors have been shown to be superior to their classical counterparts in terms of resource efficiency. Such sensors have traditionally used the time evolution of special forms of initially entangled states, adaptive measurement basis change, or the ground state of many-body systems tuned to criticality. Here, we propose a different way of doing quantum sensing which exploits the dynamics of a many-body system, initialized in a product state, along with a sequence of projective measurements in a specific basis. The procedure has multiple practical advantages as it: (i) enables remote quantum sensing, protecting a sample from the potentially invasive readout apparatus; and (ii) simplifies initialization by avoiding complex entangled or critical ground states. From a fundamental perspective, it harnesses a resource so far unexploited for sensing, namely, the residual information from the unobserved part of the many-body system after the wave-function collapses accompanying the measurements. By increasing the number of measurement sequences, through the means of a Bayesian estimator, precision beyond the standard limit, approaching the Heisenberg bound, is shown to be achievable.
