Weak measurement with orthogonal preselection and postselection
Weak measurement with orthogonal preselection and postselection
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DOI：
10.1103/physreva.86.022112
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发表时间：
2012-08-17
影响因子：
2.9
通讯作者：
Chen, Zeng-Bing
中科院分区：
文献类型：
--
作者：
Pang, Shengshi;Wu, Shengjun;Chen, Zeng-Bing
弱测量是一种新颖的量子测量方案，通常以弱值形式主义为特征。为了保证弱价值形式主义的有效性，预选和后选之间的保真度一般不能太小。本文研究了前后选择完全或渐近正交的量子比特系统的弱测量。我们将建立一个超越弱值形式的一般严格的弱测量框架，并得到前后选择完全正交时弱测量的平均输出。我们还将研究一个弱测量在前选和后选趋于正交的极限过程中的渐近性质。
Weak measurement is a novel quantum measurement scheme, which is usually characterized by the weak value formalism. To guarantee the validity of the weak value formalism, the fidelity between the preselection and the postselection should not be too small generally. In this work, we study the weak measurement on a qubit system with exactly or asymptotically orthogonal pre- and postselections. We shall establish a general rigorous framework for the weak measurement beyond the weak value formalism, and obtain the average output of a weak measurement when the pre- and postselections are exactly orthogonal. We shall also study the asymptotic behavior of a weak measurement in the limiting process that the pre- and postselections tend to be orthogonal.