The average fidelity of the teleportation of a coherent state is calculated for general Gaussian bipartite systems shared by the partners of the protocol, Alice and Bob. It is considered that the shared Gaussian bipartite modes suffer independent attenuations before the processing of Alice and Bob. Moreover the classical communication between the partners can be controlled by a gain not necessarily unitary. Comparing with the classical fidelity threshold of measure-and-prepare methods, we establish several genuinely quantum teleportation conditions which depend on the gain and the local attenuations. Considering that the gain can be tuned to maximize the bipartite state set able to genuinely quantum teleportation, a condition for teleportation robust to local attenuations is found. This condition is demonstrated to be essentially equivalent to the condition of robust Gaussian bipartite entanglement, obtained in previous articles, showing that the attenuation robustness is an entanglement property relevant for characterization and application of bipartite systems. For the derivation of the robust teleportation conditions, the Gaussian operations onto the bipartite system are thoroughly studied, so that the transformations that maintain the fidelity invariant are found. Some scenarios for different Gaussian bipartite states are presented and discussed.
Utility of noiseless linear amplification and attenuation in single-rail discrete-variable quantum communications
University of Queensland（昆士兰大学）；The Australian National University（澳大利亚国立大学）；A*STAR Quantum Innovation Centre (Q.InC), Agency for Science, Technology and Research (A*STAR)（新加坡科技研究局量子创新中心）；Q-CTRL
Robust high-fidelity teleportation of an atomic state through the detection of cavity decay
提出了一种基于腔场衰减探测的原子态量子隐形传态方案。利用单光子探测器测量偏振光子的干涉，可以将囚禁在腔中的原子的内部态离散地转移到另一个囚禁在远处腔中的原子上。与S. Bose，P.L. Knight，M.B. Plenio，and V. Vedral [Phys. Rev. Lett. 83，5158（1999）]，我们的隐形传态协议具有几乎统一的高保真度和固有的鲁棒性，例如保真度对原子位置的随机性和检测效率的不敏感性。所有这些有利的特性使得该方案在当前的实验技术下是可行的。
Universality cost of non-Gaussian enhancement in continuous-variable quantum teleportation: A fidelity--deviation trade-off
Institute for Convergence Research and Education in Advanced Technology, Yonsei University（延世大学先进技术与教育融合研究所）；Department of Statistics and Data Science, Yonsei University（延世大学统计与数据科学系）；Department of Physics, Jeju National University（济州国立大学物理系）；Department of Quantum Information, Yonsei University（延世大学量子信息系）
Time-Frequency Continuous-Variable Quantum Teleportation with Single Photons
Telecom Paris, Institut Polytechnique de Paris（巴黎电信学院，巴黎理工学院）；Centre for Nanosciences and Nanotechnology, CNRS, Université Paris-Saclay（纳米科学与工程中心，法国国家科学研究中心，巴黎萨克雷大学）
Optics-microwave entanglement and state teleportation mediated by a cavity magnomechanical system
RWTH Aachen University（亚琛工业大学）；Max Planck Institute for the Science of Light（马克斯·普朗克光科学研究所）；Delft University of Technology（代尔夫特理工大学）；Institute of Magnetism of NAS and MOS of Ukraine（乌克兰国家科学院和教育部磁性研究所）；Karlsruhe Institute of Technology（卡尔斯鲁厄理工学院）；Université de Strasbourg（斯特拉斯堡大学）
