Testing dimension and nonclassicality in communication networks
Testing dimension and nonclassicality in communication networks
复制标题
DOI：
10.1103/physreva.92.022351
复制
发表时间：
2015-08-24
影响因子：
2.9
通讯作者：
Pawlowski, Marcin
中科院分区：
文献类型：
--
作者：
Bowles, Joseph;Brunner, Nicolas;Pawlowski, Marcin
我们考虑以准备、转换和测量设备为特征的网络，其中设备通过中介物理系统交换通信。我们研究了在与设备无关的场景下，即仅基于可观测数据的情况下，测试中介系统的维度的问题。同时考虑了经典系统和量子系统，给出了解决这一问题的一般框架。然后，这些方法还可以用来证明中介系统的非典型性，给出其维度的上界。报告了几个案例研究，说明了该框架的相关性。这些例子还表明，在固定维度下，量子系统的性能大大优于经典系统。此外，与简单的准备和测量网络相比，变换设备的使用大大提高了噪声容忍度。这些结果表明，即使对于简单的网络，经典的量子系统模拟在维度方面也变得昂贵。
We consider networks featuring preparation, transformation, and measurement devices, in which devices exchange communication via mediating physical systems. We investigate the problem of testing the dimension of the mediating systems in the device-independent scenario, that is, based on observable data alone. A general framework for tackling this problem is presented, considering both classical and quantum systems. These methods can then also be used to certify the nonclassicality of the mediating systems, given an upper bound on their dimension. Several case studies are reported, which illustrate the relevance of the framework. These examples also show that, for fixed dimension, quantum systems largely outperform classical ones. Moreover, the use of a transformation device considerably improves noise tolerance when compared to simple prepare-and-measure networks. These results suggest that the classical simulation of quantum systems becomes costly in terms of dimension, even for simple networks.