We present a tomographic protocol for the characterization of multiqubit quantum channels. We discuss a specific class of input states, for which the set of Pauli measurements at the output of the channel directly relates to its Pauli transfer matrix components. We compare our results to those of standard quantum process tomography, showing an exponential reduction in the number of different experimental configurations required by a single matrix element extraction, while keeping the same number of shots. This paves the way for more efficient experimental implementations, whenever a selective knowledge of the Pauli transfer matrix is needed. We provide several examples and simulations.

中文翻译：

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泡利传输矩阵直接重建：无需全过程断层扫描的通道表征


我们提出了一种用于表征多量子位量子通道的断层扫描协议。我们讨论一类特定的输入状态，其中通道输出处的泡利测量集直接与其泡利传输矩阵分量相关。我们将我们的结果与标准量子过程断层扫描的结果进行比较，结果表明，在保持相同的发射次数的情况下，单个矩阵元素提取所需的不同实验配置的数量呈指数减少。当需要泡利传递矩阵的选择性知识时，这为更有效的实验实施铺平了道路。我们提供了几个示例和模拟。