Continuous decomposition of quantum measurements via qubit probe feedback
Continuous decomposition of quantum measurements via qubit probe feedback
复制标题
通过量子位探针反馈连续分解量子测量
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
T. Brun
中科院分区：
文献类型：
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作者：
Jan Florjanczyk;T. Brun
美国南加州大学洛杉矶，通信科学研究所，电子工程系，量子信息科学与技术研究中心，CA 90089。（日期：众所周知，任何双结果量子测量都可以使用反馈回路分解成连续随机过程。在这篇文章中，我们描述了这些分解是可能的，当反馈回路的每次迭代由与探针系统的相互作用引起的弱测量组成时。我们把自己限制在探针是一个量子位的情况下，探针和系统之间的相互作用哈密顿量是常数。我们发现，即使有能力执行任意单一脉冲在整个连续分解，只有广义测量与两个不同的奇异值是可以实现的。然而，这是苏利用量子位探针和简单的相互作用哈密顿量，有效地分解了广义量子位测量。
Center for Quantum Information Science and Technology,Communication Sciences Institute, Department of Electrical Engineering,University of Southern California Los Angeles, CA 90089, USA.(Dated: June 20, 2014)It is known that any two-outcome quantum measurement can be decomposed into a continuousstochastic process using a feedback loop. In this article, we characterize which of these decomposi-tions are possible when each iteration of the feedback loop consists of a weak measurement causedby an interaction with a probe system. We restrict ourselves to the case when the probe is a qubitand the interaction Hamiltonian between the probe and system is constant. We nd that evengiven the ability to perform arbitrary unitary pulses throughout the continuous decomposition, onlygeneralized measurements with two distinct singular values are achievable. However, this is su-cient to decompose a generalized qubit measurement using a qubit probe and a simple interactionHamiltonian.