论文标题
连续可变非高斯国家准备的模拟中驯服数值错误
Taming numerical errors in simulations of continuous variable non-Gaussian state preparation
论文作者
论文摘要
连续变量量子状态制备的数值模拟是优化现有量子信息处理协议的必要工具。这种模拟的强大仪器是Fock状态表示中的数值计算。它不可避免地利用可通过经典数字计算机实现的有限复合矢量空间对无限尺寸的Fock空间进行了近似。在此近似值中，我们分析了几种当前可用方法的准确性，用于计算截短的相干位移操作员。为了克服它们的局限性，我们根据标准矩阵指数提出了一种具有提高精度的替代方案。然后，我们采用该方法来分析非高斯国家制备方案，基于两种模式的相干位移，并随后的光子计数测量。我们比较了不同的检测机制，包括雪崩光电二极管，它们的级联反应以及在工程非线性挤压立方体的背景下解决探测器，以及在真空和单个光子状态之间构建量子样的叠加。
Numerical simulation of continuous variable quantum state preparation is a necessary tool for optimization of existing quantum information processing protocols. A powerful instrument for such simulation is the numerical computation in the Fock state representation. It unavoidably uses an approximation of the infinite-dimensional Fock space by finite complex vector spaces implementable with classical digital computers. In this approximation we analyze the accuracy of several currently available methods for computation of the truncated coherent displacement operator. To overcome their limitations we propose an alternative with improved accuracy based on the standard matrix exponential. We then employ the method in analysis of non-Gaussian state preparation scheme based on coherent displacement of a two mode squeezed vacuum with subsequent photon counting measurement. We compare different detection mechanisms, including avalanche photodiodes, their cascades, and photon number resolving detectors in the context of engineering non-linearly squeezed cubic states and construction of qubit-like superpositions between vacuum and single photon states.
