标题： 接收端通过酉变换对转移密度矩阵元素的操作 显示英文标题

标题： Operations with elements of transferred density matrix via unitary transformations at receiver side

摘要： 使用扩展接收器的单位变换工具，我们对初始发送器密度矩阵的非对角元素进行简单操作，这些元素在转移到接收器之后。 这些操作如下：将某些矩阵元素变为零，重新排列矩阵元素，并准备具有所需系数的线性组合。 我们还提出了一种求解线性代数方程组的协议，以包含两个方程的系统为例。 这些操作基于42节点的自旋-1/2链进行了数值模拟，其中包含两个量子比特的发送器和接收器。 显示英文摘要

摘要： Using the tool of unitary transformations of the extended receiver we perform simple operations with the non-diagonal elements of the initial sender's density matrix after their transferring to the receiver. These operations are following: turning some matrix elements to zero, rearranging the matrix elements and preparing their linear combinations with required coefficients. We also propose a protocol for solving a system of linear algebraic equations with a system of two equations as an example. Such operations are numerically simulated on the basis of 42-node spin-1/2 chain with the two-qubit sender and receiver.