论文标题
八个端口同伴检测器：瑕疵对量子随机数生成和检测四倍的影响
The eight-port homodyne detector: the effect of imperfections on quantum random number generation and on detection of quadratures
论文作者
论文摘要
八个端口同源探测器是一种光学电路，旨在执行光场两个四二晶的监视信号。通过使用量子bose场和量子随机演算，当在连续时间用作正交检测器时，我们给出了该设备的完整量子描述。我们可以在光学回路中处理涉及检测部分的可观察到的流动波：两种光电二极管的夫妻，输出电流的后处理。该分析包括不完美的束缚梁拆分器，检测器效率，电子噪声，相位和强度噪声，充当局部振荡器；最后噪声是通过将场相干状态的混合物作为激光组件的统计操作员进行建模的。由于监视连续时间，输出是一个随机过程，并且获得了其完整的概率分布。当输出过程在离散时间采样时，可以将量子描述简化为离散模式运算符，但以随机运算符为代价，其中还包含本地振荡器的噪声。因此，局部振荡器噪声对添加噪声（例如电子组件中的噪声）的检测结果具有截然不同的影响。作为应用程序，根据本地振荡器射击噪声，考虑了安全随机数的问题。可以通过最小内镜来量化可以生成的随机位速率；经典和量子侧信息的可能性由合适的有条件的最小渗透率考虑在内。最终速率取决于将设备的哪一部分视为安全的部分，并且认为哪些部分被视为暴露于入侵者的干预措施。在某些实验现实的情况下，计算熵损失。
The eight-port homodyne detector is an optical circuit designed to perform the monitoring of two quadratures of an optical field, the signal. By using quantum Bose fields and quantum stochastic calculus, we give a complete quantum description of this apparatus, when used as quadrature detector in continuous time. We can treat either the travelling waves in the optical circuit, either the observables involved in the detection part: two couples of photodiodes, postprocessing of the output currents. The analysis includes imperfections, such as not perfectly balanced beam splitters, detector efficiency, electronic noise, phase and intensity noise in the laser acting as local oscillator; this last noise is modelled by using mixtures of field coherent states as statistical operator of the laser component. Due to the monitoring in continuous time, the output is a stochastic process and its full probability distribution is obtained. When the output process is sampled at discrete times, the quantum description can be reduced to discrete mode operators, but at the price of having random operators, which contain also the noise of the local oscillator. Consequently, the local oscillator noise has a very different effect on the detection results with respect to an additive noise, such as the noise in the electronic components. As an application, the problem of secure random number generation is considered, based on the local oscillator shot noise. The rate of random bits that can be generated is quantified by the min-entropy; the possibility of classical and quantum side information is taken into account by suitable conditional min-entropies. The final rate depends on which parts of the apparatus are considered to be secure and on which ones are considered to be exposed to the intervention of an intruder. In some experimentally realistic situations, the entropy losses are computed.
