arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0906.3002quant-ph
收藏

选择性和高效的量子过程层析成像

Selective and Efficient Quantum Process Tomography

Ariel Bendersky, Fernando Pastawski, Juan Pablo Paz

摘要:

在本文中,我们详细描述和推广的量子过程层析成像方法,提出了在[A。Bendersky,F. Pastawski,J.P. Paz,Physical Review Letters 100,190403(2008)]。该方法能够有效地估计任何元素的$χ$ -矩阵的量子过程。这些元素被估计为实验结果的平均值,其精度由实验的重复次数固定。实现它所需的资源与系统的量子位数成多项式关系。$χ$ -矩阵的所有对角元素的估计可以在没有任何辅助量子比特的情况下有效地进行。反过来,所有非对角元素的估计需要额外的干净量子位。该方法的关键思想,即基于有效的估计随机抽样超过一组状态形成一个2-设计,进行了详细描述。明确示出了用于制备和检测这样的状态的有效方法。

英文摘要:

In this paper we describe in detail and generalize a method for quantum process tomography that was presented in [A. Bendersky, F. Pastawski, J. P. Paz, Physical Review Letters 100, 190403 (2008)]. The method enables the efficient estimation of any element of the $χ$--matrix of a quantum process. Such elements are estimated as averages over experimental outcomes with a precision that is fixed by the number of repetitions of the experiment. Resources required to implement it scale polynomically with the number of qubits of the system. The estimation of all diagonal elements of the $χ$--matrix can be efficiently done without any ancillary qubits. In turn, the estimation of all the off-diagonal elements requires an extra clean qubit. The key ideas of the method, that is based on efficient estimation by random sampling over a set of states forming a 2--design, are described in detail. Efficient methods for preparing and detecting such states are explicitly shown.

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。

↑