论文标题
忠诚和敏感性对Ancilla辅助过程断层扫描
Faithfulness and sensitivity for ancilla-assisted process tomography
论文作者
论文摘要
一个能够包含在系统上作用的未知量子渠道的完整信息的系统 - 齐甲状态被称为忠实。 d'Ariano和presti证明的状态忠诚与相应的Jamiolkowski图的可逆性之间的等价性是对辅助辅助过程断层扫描的有用表征，尽管该证明是不完整的，尽管他们假定痕量非inncreas noncreas noncreas量子操作，而不是量子通道。我们完成了等效性的证明，并将忠诚的概括引入各种类别的量子通道。我们还探讨了一个更通用的概念，我们称为灵敏度，量子状态的量子状态的特性会因量子通道的任何非平凡作用而改变。我们通过表征重要类别的量子通道，例如Unital通道，随机统一操作和统一操作来研究它们的关系。它们之间的意外（非）等价结果通过表明我们只需要两类量子状态来表征对量子通道的各种子类的表征，从而阐明了量子通道的结构。例如，它揭示了量子过程断层扫描与量子相关性之间的关系，因为事实证明，只有完全没有局部经典观察的两分状状态才能使用来感知Unital通道的效果。
A system-ancilla bipartite state capable of containing the complete information of an unknown quantum channel acting on the system is called faithful. The equivalence between faithfulness of state and invertibility of the corresponding Jamiolkowski map proved by D'Ariano and Presti has been a useful characterization for ancilla-assisted process tomography albeit the proof was incomplete as they assumed trace nonincreasing quantum operations, not quantum channels. We complete the proof of the equivalence and introduce the generalization of faithfulness to various classes of quantum channels. We also explore a more general notion we call sensitivity, the property of quantum state being altered by any nontrivial action of quantum channel. We study their relationship by characterizing both properties for important classes of quantum channels such as unital channels, random unitary operations and unitary operations. Unexpected (non-)equivalence results among them shed light on the structure of quantum channels by showing that we need only two classes of quantum states for characterizing quantum states faithful or sensitive to various subclasses of quantum channels. For example, it reveals the relation between quantum process tomography and quantum correlation as it turns out that only bipartite states that has no local classical observable at all can be used to sense the effect of unital channels.
