论文标题
借助量子状态测量评估随机性
Assessing randomness with the aid of quantum state measurement
论文作者
论文摘要
随机性是科学，密码学，工程和信息技术的宝贵资源。由于单个量子过程的不确定性，随机性的量子机械源具有吸引力。在这里，我们考虑从光子上的极化测量中产生随机位。我们首先提出了关于这种测量中固有的量子随机性如何与量子相干性连接的教学讨论，以及如何根据量子状态和相关的熵值（称为最小entropy）进行量化。然后，我们通过执行适合本科实验室的一系列单光子实验来探索这些概念。我们在不同的无输入状态和纠缠状态中准备光子，并通过层压术测量这些状态。我们使用有关量子状态的信息来确定最小内侧面的最小随机性，从给定的光子状态产生的最小随机性通过不同的生成测量结果。这有助于评估量子随机性的存在以及确保随机位源的质量和安全性。
Randomness is a valuable resource in science, cryptography, engineering, and information technology. Quantum-mechanical sources of randomness are attractive because of the indeterminism of individual quantum processes. Here we consider the production of random bits from polarization measurements on photons. We first present a pedagogical discussion of how the quantum randomness inherent in such measurements is connected to quantum coherence, and how it can be quantified in terms of the quantum state and an associated entropy value known as min-entropy. We then explore these concepts by performing a series of single-photon experiments that are suitable for the undergraduate laboratory. We prepare photons in different nonentangled and entangled states, and measure these states tomographically. We use the information about the quantum state to determine, in terms of the min-entropy, the minimum amount of randomness produced from a given photon state by different bit-generating measurements. This is helpful in assessing the presence of quantum randomness and in ensuring the quality and security of the random-bit source.
