Article
Physics, Multidisciplinary
Amir Arqand, Laleh Memarzadeh, Stefano Mancini
Summary: This paper investigates the LOCC-assisted quantum capacity of a bosonic dephasing channel with energy constraint on the input states. The analysis focuses on the energy-constrained squashed entanglement of the channel, which serves as an upper bound for the energy-constrained LOCC-assisted quantum capacity. To overcome the challenge of computing the energy-constrained squashed entanglement, an upper bound is derived and its tightness is discussed. The optimal input state is proven to be diagonal in the Fock basis. Furthermore, explicit upper and lower bounds for the energy-constrained LOCC-assisted quantum capacity of the bosonic dephasing channel are derived using two specific examples of squashing channels and their relationship to the quantum capacity with different noise parameters is examined.
Article
Quantum Science & Technology
Fakhar Zaman, Een-Kee Hong, Hyundong Shin
Summary: This paper investigates the distinguishability of Bell-type states using local operations and classical communication without particle exchange, starting from the local distinguishability of orthogonal Bell-type states and generalizing it to non-orthogonal Bell-type states with nonzero fidelity.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Physics, Multidisciplinary
Jef Pauwels, Stefano Pironio, Emmanuel Zambrini Cruzeiro, Armin Tavakoli
Summary: Entanglement can enhance classical communication efficiency, and its adaptive usage improves success probability and becomes a stronger resource.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Atanu Bhunia, Indranil Biswas, Indrani Chattopadhyay, Debasis Sarkar
Summary: This paper investigates the number of measurement and communication rounds needed to implement a discrimination task by LOCC in distinguishing a set of pure bipartite orthogonal quantum states. It shows that the round numbers can be reduced by using entanglement as a resource, and the amount of entanglement assistance affects the number of LOCC rounds needed for the discrimination task.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2023)
Article
Computer Science, Information Systems
Kun Wang, Masahito Hayashi
Summary: The study focuses on classical communication over a noisy quantum channel with preshared bipartite states between sender and receiver, using different encoding strategies. The main result is a capacity formula for strategy iii) that serves as a sharp dividing line between achievable and unachievable rates of communication. Results show that the capacity difference between strategy i) and strategy iii) is upper bounded by the discord of formation of the preshared state, and that strategy ii) does not have an advantage over strategy i) in the weak converse regime.
IEEE TRANSACTIONS ON INFORMATION THEORY
(2021)
Article
Multidisciplinary Sciences
Jihao Fan, Jun Li, Yongbin Zhou, Min-Hsiu Hsieh, H. Vincent Poor
Summary: This paper proposes a new method called entanglement-assisted concatenated quantum codes (EACQCs) and shows that it has significant advantages over standard concatenated quantum codes (CQCs). EACQCs can beat the nondegenerate Hamming bound for entanglement-assisted quantum error-correction codes (EAQECCs) and have better parameters. Moreover, they require fewer entangled pairs to begin with and enable entanglement-assisted quantum communication even with noisy entanglement bits (ebits). In addition, EACQCs can outperform CQCs in entanglement fidelity over depolarizing channels.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Physics, Multidisciplinary
Ivan B. Djordjevic
Summary: In this paper, an entanglement assisted joint monostatic-bistatic quantum radar scheme is proposed, which outperforms conventional radars in terms of sensitivity.
Article
Physics, Multidisciplinary
Ivan B. Djordjevic
Summary: Entanglement-based quantum sensors have better sensitivity in noisy and lossy conditions compared to classical sensors, and an entanglement-assisted (EA) multistatic radar outperforms other radars significantly in performance.
Article
Physics, Multidisciplinary
Indranil Biswas, Atanu Bhunia, Indrani Chattopadhyay, Debasis Sarkar
Summary: No pure entangled state can be distilled from a 2 (R) 2 or 2 (R) 3 mixed state by separable operations. In 3 (R) 3, pure entanglement can be distilled by separable operation but not by LOCC. In this letter, we proved the conjecture (Chitambar and Duan (2009) [21]) that it is possible to distill pure entanglement for 2 (R) 4 system by LOCC and further improve these in higher dimensions to distill a pure entangled state of Schmidt rank d from a m (R) n mixed state by separable operation when m + n ≥ 3d. We found results for tripartite systems with target state d-level GHZ-type state. These results provide a class of systems where separable operation is strictly stronger than LOCC.
Article
Physics, Multidisciplinary
Carlos Vieira, Carlos de Gois, Lucas Pollyceno, Rafael Rabelo
Summary: Prepare-and-measure scenarios are the basic building blocks of communication tasks and can be used to analyze various classical and quantum protocols. This study explores scenarios where entanglement is used as a resource and provides answers to important questions.
NEW JOURNAL OF PHYSICS
(2023)
Article
Optics
Qing-Shou Tan, Mao Zhang, Yu Chen, Jie-Qiao Liao, Jing Liu
Summary: By introducing combined controls performed at different time intervals in a collective spin system, the generation and storage performance of spin squeezing can be improved. This approach provides not only a comparable minimum value of the squeezing parameter over time compared to full-time varying controls, but also offers better lifetime and larger amount of squeezing.
Article
Physics, Multidisciplinary
Mohsen Falamarzi Askarani, Kaushik Chakraborty, Gustavo Castro do Amaral
Summary: The proposed quantum network architecture utilizes quantum processing devices based on NV- color centers as quantum routers, with long-distance entanglement distribution enabled by spectrally-multiplexed quantum repeaters based on absorptive quantum memories and imperfect entangled photon-pair sources. The inclusion of a quantum buffer structure between repeaters and routers improves the achievable entanglement distribution rates in the network.
NEW JOURNAL OF PHYSICS
(2021)
Article
Optics
Donato Farina, Vasco Cavina, Marco G. Genoni, Vittorio Giovannetti
Summary: This study analyzes the capability of discriminating the statistical nature of a thermal bath in the presence of different types of side resources. It finds that the presence of an auxiliary environment can be beneficial and significantly improve the discrimination performance.
Article
Computer Science, Information Systems
Ivan B. Djordjevic
Summary: Entanglement assisted bistatic quantum radar applications are studied in this paper. By employing optical phase conjugation and classical coherent detection, the proposed target detection scheme shows significantly improved detection probability compared to classical and coherent states-based quantum detection schemes. The evaluation of the scheme takes into account lossy and noisy Bosonic channel and imperfect distribution of entanglement.
Article
Quantum Science & Technology
Soumik Adhikary
Summary: The study introduces a supervised quantum classifier training algorithm that utilizes the property of quantum entanglement, achieving successful binary classification on benchmark datasets.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Physics, Multidisciplinary
Yi Shen, Lin Chen
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2018)
Article
Mathematics
Kai Wang, Lin Chen, Yi Shen, Yize Sun, Li-Jun Zhao
Summary: The study focuses on the 4-qubit unextendible product bases and presents specific examples and constructions in various contexts. Additionally, a geometric measure of a special PPT entangled state is analytically derived.
LINEAR & MULTILINEAR ALGEBRA
(2021)
Article
Physics, Multidisciplinary
Yi Shen, Lin Chen
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2020)
Article
Mathematics, Applied
Yingkai Ouyang, Yi Shen, Lin Chen
LINEAR ALGEBRA AND ITS APPLICATIONS
(2020)
Article
Physics, Multidisciplinary
Yi Shen, Lin Chen, Li-Jun Zhao
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2020)
Article
Quantum Science & Technology
Fei Shi, Yi Shen, Lin Chen, Xiande Zhang
QUANTUM INFORMATION PROCESSING
(2020)
Article
Mathematics, Applied
Lilong Qian, Lin Chen, Delin Chu, Yi Shen
Summary: Pure entangled states are crucial in quantum information, and the asymptotic extraction of pure entangled states from mixed states via local operations and classical communication is discussed. Recent research has demonstrated the validity of certain conjectures under specific conditions.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2021)
Article
Quantum Science & Technology
Yi Shen, Lin Chen
Summary: This work focuses on AME states in tripartite heterogeneous systems, introducing irreducible AME states and a magic solution array to construct AME states in systems with large local dimensions. It also explores the connection between heterogeneous AME states and multi-isometry matrices, and their application in quantum steering.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Computer Science, Information Systems
Fei Shi, Yi Shen, Lin Chen, Xiande Zhang
Summary: This study explores k-uniform states in heterogeneous systems, presenting constructions for 2-uniform and 3-uniform states as well as methods for generating (k-1)-uniform states from k-uniform states. Results on the nonexistence of absolutely maximally entangled states are also provided, along with connections to quantum information masking.
IEEE TRANSACTIONS ON INFORMATION THEORY
(2022)
Article
Physics, Multidisciplinary
Lin Zhang, Ming-Jing Zhao, Lin Chen, Hua Xiang, Yi Shen
Summary: The paper focuses on the study of partial-transpose (PT)-moments of two-qubit states and provides a complete description of the region corresponding to these moments. It also analyzes the states corresponding to the boundary points of the region and the border lines between separable and entangled states. The results are extended to detect the entanglement of multiqubit states.
ANNALEN DER PHYSIK
(2022)
Article
Physics, Multidisciplinary
Yi Shen, Lin Chen, Li Yu
Summary: This study mainly investigates the classification of genuine multipartite unitary gates of Schmidt rank two. By introducing the concept of singular number and determining its accurate range, we classify these unitary gates. Additionally, we extend the study to three-qubit diagonal unitary gates and provide their characteristics and conditions.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Mathematics
Changchun Feng, Lin Chen, Chang Xu, Yi Shen
Summary: The study investigates the inertia of entanglement witnesses constructed by the partial transpose, particularly focusing on the bipartite NPT states of a two-qutrit system. The results are also extended to high-dimensional states.
LINEAR & MULTILINEAR ALGEBRA
(2022)
Article
Optics
Li-Jun Zhao, Lin Chen, Yu-Min Guo, Kai Wang, Yi Shen, Shao-Ming Fei
Article
Optics
Lin Chen, Delin Chu, Lilong Qian, Yi Shen