Detection and quantification of entanglement with measurement-device-independent and universal entanglement witness

作     者：Zhi-Jin Ke Yi-Tao Wang Shang Yu Wei Liu Yu Meng Zhi-Peng Li Hang Wang Qiang Li Jin-Shi Xu Ya Xiao Jian-Shun Tang Chuan-Feng Li Guang-Can Guo 柯芝锦;王轶韬;俞上;刘伟;孟雨;李志鹏;汪航;李强;许金时;肖芽;唐建顺;李传锋;郭光灿

作者机构：CAS Key Laboratory of Quantum InformationUniversity of Science and Technology of ChinaHefei 230026China CAS Center For Excellence in Quantum Information and Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China Department of PhysicsOcean University of ChinaQingdao 266100China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2020年第29卷第8期

页      面：143-150页

核心收录：

学科分类：07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 070201[理学-理论物理] 0704[理学-天文学] 0702[理学-物理学] 

基　　金：the National Key Research and Development Program of China(Grant No.2016YFA0302700) the National Natural Science Foundation of China(Grant Nos.11674304,11822408,11774335,61490711,11474267,11821404,and 91321313) the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2017492) the Foundation for Scientific Instrument and Equipment Development of Chinese Academy of Sciences(Grant No.YJKYYQ20170032) the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(Grant No.QYZDY-SSW-SLH003) the Fundamental Research Funds for the Central Universities,China(Grant No.WK2470000026) 

主　　题：entanglement witness entanglement detection entanglement quantification measurement-deviceindependent 

摘      要：Entanglement is the key resource in quantum information processing,and an entanglement witness(EW)is designed to detect whether a quantum system has any ***,prior knowledge of the target states should be known first to design a suitable EW,which weakens this ***,a recent theory shows that it is possible to design a universal entanglement witness(UEW)to detect negative-partial-transpose(NPT)entanglement in unknown bipartite states with measurement-device-independent(MDI)*** outcome of a UEW can also be upgraded to be an entanglement *** this study,we experimentally design and realize an MDI UEW for two-qubit entangled *** of the tested states are well-detected without any prior *** also show that it is able to quantify entanglement by comparing it with concurrence estimated through state *** relation between them is also *** entire experimental framework ensures that the UEW is MDI.