Experimental Test of the State Estimation-Reversal Tradeoff Relation in General Quantum Measurements
Experimental Test of the State Estimation-Reversal Tradeoff Relation in General Quantum Measurements
复制标题
一般量子测量中状态估计-反转权衡关系的实验测试
DOI：
10.1103/physrevx.4.021043
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发表时间：
2014-06
影响因子：
12.5
通讯作者：
Kedem, Yaron
中科院分区：
文献类型：
--
作者：
Li, Mi-Feng;Zha, Guo-Wei;Niu, Zhi-Chuan;Kedem, Yaron
当测量强度有限时，仅提取有关初始状态的部分信息，并且相应地，有可能扭转其对系统的影响并恢复原始状态。最近，Y.K. Cheong 和 S. W. Lee 用权衡关系对这种互补关系进行了清晰、直接的定量描述。 [物理。莱特牧师。 109, 150402 (2012)]。在这里，使用来自量子点的偏振编码单光子通过实验验证了这种权衡关系。实现了代表完整范围的测量算子，从不影响系统到投影到单一偏振态。此外，对于每个测量算子，还实现了最佳反转算子。权衡关系的上限映射到代表测量强度的实验参数。我们的结果补充了理论工作，并提供了一般量子测量的实际表征。
When a measurement has limited strength, only partial information, regarding the initial state, is extracted, and, correspondingly, there is a probability to reverse its effect on the system and retrieve the original state. Recently, a clear and direct quantitative description of this complementary relationship, in terms of a tradeoff relation, was developed by Y. K. Cheong and S. W. Lee. [Phys. Rev. Lett. 109, 150402 (2012)]. Here, this tradeoff relation is experimentally verified using polarization-encoded single photons from a quantum dot. Measurement operators representing a complete range, from not affecting the system to a projection to a single polarization state, are realized. In addition, for each measurement operator, an optimal reversal operator is also implemented. The upper bound of the tradeoff relation is mapped to experimental parameters representing the measurement strength. Our results complement the theoretical work and provide a hands-on characterization of general quantum measurements.