论文标题
使用最佳策略来标准化量子状态验证
Towards the standardization of quantum state verification using optimal strategies
论文作者
论文摘要
用于生成纠缠状态的量子设备已被广泛研究并广泛使用。因此，有必要验证这些设备在指定的情况下真正可靠，有效地工作。在这里，我们在实验上使用局部测量（非适应性）和带有光子平台的主动馈送操作（自适应）和主动馈送操作（自适应）实现了最近提出的两量纠缠状态验证策略。需要大约3283/536的副本数量（$ n $）才能获得99％的信心来验证非适应性/适应性策略的目标量子状态。这些最佳策略提供了$ n $（$ε$ $ \ sim $ $ $ n^r $）的不忠$ε$的Heisenberg缩放，参数$ r = -1 $，超过了标准量子限制，$ r = -0.5 $。我们通过实验性地获得$ r = -0.88 \ pm $ 0.03和$ -0.78 \ pm $ 0.07的缩放参数分别用于非自适应和自适应策略。我们的实验工作可以用作验证量子状态的标准化程序。
Quantum devices for generating entangled states have been extensively studied and widely used. As so, it becomes necessary to verify that these devices truly work reliably and efficiently as they are specified. Here, we experimentally realize the recently proposed two-qubit entangled state verification strategies using both local measurements (nonadaptive) and active feed-forward operations (adaptive) with a photonic platform. About 3283/536 number of copies ($N$) are required to achieve a 99% confidence to verify the target quantum state for nonadaptive/adaptive strategies. These optimal strategies provide the Heisenberg scaling of the infidelity $ε$ as a function of $N$ ($ε$ $\sim$ $N^r$) with the parameter $r=-1$, exceeding the standard quantum limit with $r=-0.5$. We experimentally obtain the scaling parameter of $r=-0.88\pm$0.03 and $-0.78\pm$0.07 for nonadaptive and adaptive strategies, respectively. Our experimental work could serve as a standardized procedure for the verification of quantum states.
