量子态线性和非线性泛函的直接估计
Direct estimations of linear and non-linear functionals of a quantum state
摘要：
我们提出了一个简单的量子网络，基于受控交换门，可以提取某些性质的量子态，而不求助于量子层析。它可以用来作为一个基本的积木直接量子估计的线性和非线性泛函的任何密度算子。该网络具有许多潜在的应用，从纯度测试和本征值估计到直接表征量子信道的某些性质。拟议网络的实验实现在目前正在开发的量子技术的范围内。
英文摘要：
We present a simple quantum network, based on the controlled-SWAP gate, that can extract certain properties of quantum states without recourse to quantum tomography. It can be used used as a basic building block for direct quantum estimations of both linear and non-linear functionals of any density operator. The network has many potential applications ranging from purity tests and eigenvalue estimations to direct characterization of some properties of quantum channels. Experimental realizations of the proposed network are within the reach of quantum technology that is currently being developed.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
