发表机构
Korea Institute of Science and Technology (KIST); Kyung Hee University; Korea Institute of Science and Technology Information (KISTI)（韩国科学技术院; 庆熙大学; 韩国科学技术信息研究院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究针对三量子比特纯态受控隐形传态，推导了保真度偏差下界，发现控制器协助对保真度偏差的影响与最大平均保真度不同，揭示了控制对二者的对比效应。
AI 中文摘要
隐形传态性能通常由平均隐形传态保真度表征，而其在输入态上的变化则提供了由保真度偏差捕获的额外信息。在受控隐形传态中，控制器的测量会通过其测量结果引入额外的保真度变化源。我们研究了三量子比特纯态下受控隐形传态中的保真度偏差，推导了保真度偏差的下界，并表明该下界可与最大平均隐形传态保真度同时达到。然而，在达到最大平均保真度的测量中，保真度偏差会因控制器测量的不同而变化。我们通过将受控隐形传态与使用约化态的直接隐形传态进行比较，进一步考察了控制器协助的效应：与最大平均保真度不会因控制器协助而降低不同，最小保真度偏差不一定会因控制器协助而减小，尤其是对于任意W类纯态，控制器协助无法减小保真度偏差。这些结果揭示了控制在受控隐形传态中对隐形传态保真度及其偏差的对比效应。
英文摘要
Teleportation performance is commonly characterized by the average teleportation fidelity, while its variation over input states provides additional information captured by the fidelity deviation. In controlled teleportation, the controller's measurement introduces an additional source of fidelity variation through its measurement outcomes. We investigate the fidelity deviation in controlled teleportation with three-qubit pure states. We derive a lower bound on the fidelity deviation and show that it is attainable together with the maximal average teleportation fidelity. Among the measurements attaining the maximal average fidelity, however, the fidelity deviation can vary depending on the controller's measurement. We further examine the effect of controller assistance by comparing controlled teleportation with direct teleportation using the reduced state. Unlike the maximal average fidelity, which cannot decrease with controller assistance, the minimal fidelity deviation is not necessarily reduced by controller assistance. In particular, for any W-class pure state, controller assistance cannot reduce the fidelity deviation. These results reveal contrasting effects of control on teleportation fidelity and its deviation in controlled teleportation.
Comments7 pages, 2 figures
