Given $n$ copies of an unknown quantum state $ρ\in\mathbb{C}^{d\times d}$, quantum state certification is the task of determining whether $ρ=ρ_0$ or $\|ρ-ρ_0\|_1>\varepsilon$, where $ρ_0$ is a known reference state. We study quantum state certification using unentangled quantum measurements, namely measurements which operate only on one copy of $ρ$ at a time. When there is a common source of shared randomness available and the unentangled measurements are chosen based on this randomness, prior work has shown that $Θ(d^{3/2}/\varepsilon^2)$ copies are necessary and sufficient. This holds even when the measurements are allowed to be chosen adaptively. We consider deterministic measurement schemes (as opposed to randomized) and demonstrate that $Θ(d^2/\varepsilon^2)$ copies are necessary and sufficient for state certification. This shows a separation between algorithms with and without shared randomness.
We develop a unified lower bound framework for both fixed and randomized measurements, under the same theoretical framework that relates the hardness of testing to the well-established Lüders rule. More precisely, we obtain lower bounds for randomized and fixed schemes as a function of the eigenvalues of the Lüders channel which characterizes one possible post-measurement state transformation.
Device-independent certification of maximal randomness from pure entangled two-qutrit states using non-projective measurements
虽然最近已经证明了如何以设备无关的方式证明任何纯两量子比特纠缠态的最大随机性[E。Woodhead等人，Phys. Rev. Research 2，042028（R）（2020）]，来自更高局部维度的纠缠态的最佳随机性认证的问题仍然是开放的。在这里，我们介绍了一种方法的设备无关的认证的最大可能数量的$2\log_23$随机比特使用纯二分纠缠两quutrit状态和极端的九个结果一般非投影测量。为此，我们利用最近在[S. Sarkar等人，arXiv：2110.15176]，它结合了一种设备无关的方法来证明三维希尔伯特空间中的完全Weyl-Heisenberg基，以及一种单侧设备无关的方法来证明两个quitri部分纠缠态。
Lund University（隆德大学）；University of Jyväskylä（于韦斯屈莱大学）；Technical University of Denmark（丹麦技术大学）；Korea Advanced Institute of Science and Technology (KAIST)（韩国科学技术院）
Semi-device-independent randomness certification on discretized continuous-variable platforms
Federal University of Rio Grande do Norte（北里奥格兰德联邦大学）；International Institute of Physics, Federal University of Rio Grande do Norte（北里奥格兰德联邦大学国际物理研究所）；QuIIN - Quantum Industrial Innovation, EMBRAPII CIMATEC Competence Center in Quantum Technologies, SENAI CIMATEC（QuIIN量子工业创新，EMBRAPII CIMATEC量子技术能力中心，SENAI CIMATEC）；Center for Macroscopic Quantum States bigQ, Department of Physics, Technical University of Denmark（丹麦技术大学宏观量子态bigQ研究中心）
Device-independent certification of two bits of randomness from one entangled bit and Gisin's elegant Bell inequality
我们证明，正如Ac\'ın等人[Phys. Rev. A 93，040102（R）（2016）]所证明的那样，可以使用Gisin优雅的贝尔不等式的最大量子违反，以设备无关的方式从一位纠缠中证明两位随机性。这表明了一个令人惊讶的最大纠缠之间的联系，相互无偏基地的完整集合，对称信息完全的积极运营商值的措施，一方面，和最佳的方式证明最大的随机性，另一方面。
Self-testing of any pure entangled state with minimal number of measurements and optimal randomness certification in one-sided device-independent scenario
Randomness Certification and Trade-offs in the Prepare-and-Broadcast Scenario
Federal University of Rio Grande do Norte（北里奥格兰德联邦大学）；International Institute of Physics, Federal University of Rio Grande do Norte（北里奥格兰德联邦大学国际物理研究所）；QuIIN - Quantum Industrial Innovation, EMBRAPII CIMATEC Competence Center in Quantum Technologies, SENAI CIMATEC（QuIIN-量子工业创新，EMBRAPII CIMATEC量子技术能力中心，SENAI CIMATEC）；Center for Macroscopic Quantum States bigQ, Department of Physics, Technical University of Denmark（丹麦技术大学物理学系宏观量子态bigQ中心）
Entanglement in the energy-constrained prepare-and-measure scenario: applications to randomness certification and channel discrimination
ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology（光子科学研究所，巴塞罗那科学技术研究院）；Quside Technologies S.L.（Quside科技有限公司）；ICREA - Institució Catalana de Recerca i Estudis Avançats（加泰罗尼亚研究高级机构）
Quantum randomness certification with untrusted measurements and few probe states
Keio University（庆应义塾大学）；Lund University（隆德大学）；ICFO - Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology（ICFO-光子科学研究所，巴塞罗那科学技术研究院）；Quantinuum；Technical University of Denmark（丹麦技术大学）
Bell inequalities tailored to optimal global randomness certification
ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology（ICFO-光子科学研究所，巴塞罗那科技研究所）；Center for Quantum-Enabled Computing, Center for Theoretical Physics, Polish Academy of Sciences（波兰科学院量子使能计算中心，理论物理中心）；Department of Algorithms and System Modeling, Faculty of Electronics, Telecommunications and Informatics, Gdańsk University of Technology（格但斯克理工大学电子、电信与信息学院算法与系统建模系）；ICREA-Institucio Catalana de Recerca i Estudis Avançats（ICREA-加泰罗尼亚高级研究学院）
Semi-device-independent quantum randomness certification in semiconductor spin-noise measurements
School of Physical and Chemical Sciences, Queen Mary University of London（伦敦大学玛丽女王学院物理与化学科学学院）；Experimentelle Physik 2, Technische Universität Dortmund（多特蒙德工业大学第二物理系）
Noise robustness of three outcome Bell certified quantum randomness
ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology（光子科学研究所，巴塞罗那科学技术学院）；Center for Theoretical Physics, Polish Academy of Sciences（波兰科学院理论物理中心）；Department of Algorithms and System Modeling, Faculty of Electronics, Telecommunications and Informatics, Gdańsk University of Technology（格但斯克理工大学电子、电信与信息学院算法与系统建模系）；ICREA-Institucio Catalana de Recerca i Estudis Avançats（加泰罗尼亚研究与高级研究学院）
