论文标题
“无相互作用”频道歧视
'Interaction-Free' Channel Discrimination
论文作者
论文摘要
在这项工作中，我们调查了一个问题，哪些对象可以通过“无相互作用”测量完美地区分。为此，我们将Elitzur-Vaidman炸弹 - tester实验解释为量子通道歧视问题，并将“无相互作用”测量的概念推广到任意量子通道。我们的主要结果是一个必要和足够的标准，因为它可以或不可能以“无相互作用”方式区分量子通道（即，可以任意使歧视误差概率和“相互作用”概率任意地使量子通道（即，使歧视误差概率和“相互作用”概率都很小）。对于我们的病情成立的情况，我们使用属性设计了一个明确的协议，即两个概率都将零数量的频道用途（$ n $）接近零。更具体地说，我们的协议中的“交互”概率衰减为$ \ frac {1} {n} $，我们表明此速率是最佳实现的速率。此外，我们的协议最多只需要一个辅助量子，因此在近期实验中可以实现。对于我们的病情不存在的情况，我们证明了一种不平等，可以量化错误概率和“相互作用”概率之间的权衡。
In this work, we investigate the question, which objects one can discriminate perfectly by 'interaction-free' measurements. To this end, we interpret the Elitzur-Vaidman bomb-tester experiment as a quantum channel discrimination problem and generalize the notion of 'interaction-free' measurement to arbitrary quantum channels. Our main result is a necessary and sufficient criterion for when it is possible or impossible to discriminate quantum channels in an 'interaction-free' manner (i.e., such that the discrimination error probability and the 'interaction' probability can be made arbitrarily small). For the case where our condition holds, we devise an explicit protocol with the property that both probabilities approach zero with an increasing number of channel uses, $N$. More specifically, the 'interaction' probability in our protocol decays as $\frac{1}{N}$ and we show that this rate is the optimal achievable one. Furthermore, our protocol only needs at most one ancillary qubit and might thus be implementable in near-term experiments. For the case where our condition does not hold, we prove an inequality that quantifies the trade-off between the error probability and the 'interaction' probability.
