标题： 线性光学中成功概率的上界 显示英文标题

标题： Upper bounds on success probabilities in linear optics

摘要： 我们开发了一种抽象的方法来定义旨在执行量子信息任务（如量子门）的线性光学网络。 我们将主要关注非线性符号移位门，但显然所有其他门都可以以类似的方式处理。 该抽象方案非常适合分析和数值研究，因为它减少了通用设置中的参数数量。 通过这种方法，我们数值上并部分地分析地展示了对于一大类状态，生成非线性符号移位门的成功概率不超过1/4，据我们所知，这是迄今为止最强的界限。 显示英文摘要

摘要： We develop an abstract way of defining linear-optics networks designed to perform quantum information tasks such as quantum gates. We will be mainly concerned with the nonlinear sign shift gate, but it will become obvious that all other gates can be treated in a similar manner. The abstract scheme is extremely well suited for analytical as well as numerical investigations since it reduces the number of parameters for a general setting. With that we show numerically and partially analytically for a wide class of states that the success probability of generating a nonlinear sign shift gate does not exceed 1/4 which to our knowledge is the strongest bound to date.