论文标题
散射作为量子计量问题：量子步行方法
Scattering as a quantum metrology problem: a quantum walk approach
论文作者
论文摘要
我们通过一维屏障电位在一组离散位置上通过一维屏障电位来解决量子粒子的散射。我们将问题形式化为具有杂质在晶格上的连续时间量子行走，并使用量子渔民信息作为均值来量化屏障高度估计的最大可能准确性。我们引入了助行器的合适初始状态，并得出散射状态的反射和传输概率。我们表明，虽然量子渔民信息受初始波数据包的宽度和中心动量的影响，但对于量子信噪比而言，这种依赖性较弱。我们还表明，二分法位置测量提供了几乎最佳的检测方案。
We address the scattering of a quantum particle by a one-dimensional barrier potential over a set of discrete positions. We formalize the problem as a continuous-time quantum walk on a lattice with an impurity, and use the quantum Fisher information as a mean to quantify the maximal possible accuracy in the estimation of the height of the barrier. We introduce suitable initial states of the walker and derive the reflection and transmission probabilities of the scattered state. We show that while the quantum Fisher information is affected by the width and central momentum of the initial wave packet, this dependency is weaker for the quantum signal-to-noise ratio. We also show that a dichotomic position measurement provides a nearly optimal detection scheme.
