Resource theory of quantum non-Gaussianity and Wigner negativity
Resource theory of quantum non-Gaussianity and Wigner negativity
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DOI：
10.1103/physreva.98.052350
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发表时间：
2018-11-28
影响因子：
2.9
通讯作者：
Ferraro, Alessandro
中科院分区：
文献类型：
--
作者：
Albarelli, Francesco;Genoni, Marco G.;Ferraro, Alessandro
我们为连续变量系统开发了一个资源理论，该理论基于当前量子技术中常规可用的操作。特别地，自由操作的集合是凸的，并且包括二次变换和条件粗粒度测量。本理论适合于将量子非高斯性和维格纳负性作为资源进行量化，这取决于自由态集的选择-即，高斯态的凸船体或正Wigner函数态。在证明该理论不允许最大资源状态之后，我们定义了一个可计算的资源单调性--维格纳对数负性。我们使用后者来评估实验相关状态的资源内容-例如，增加光子、减少光子、反相和猫状态，并找到一些资源集中协议的最佳工作点。我们设想这个框架的应用程序，以亚通用和通用的量子信息处理连续变量。
We develop a resource theory for continuous-variable systems grounded on operations routinely available within current quantum technologies. In particular, the set of free operations is convex and includes quadratic transformations and conditional coarse-grained measurements. The present theory lends itself to quantify both quantum non-Gaussianity and Wigner negativity as resources, depending on the choice of the free-state set-i.e., the convex hull of Gaussian states or the states with positive Wigner function, respectively. After showing that the theory admits no maximally resourceful state, we define a computable resource monotone-the Wigner logarithmic negativity. We use the latter to assess the resource content of experimentally relevant states-e.g., photon-added, photon-subtracted, cubic-phase, and cat states-and to find optimal working points of some resource concentration protocols. We envisage applications of this framework to subuniversal and universal quantum information processing over continuous variables.