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Related papers: Channel purification via continuous-variable quant…

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Quantum metrology stands as a leading application of quantum science and technology, yet noise often constrains its precision and sensitivity. In near-term quantum metrology, existing protocols largely depend on virtual state purification,…

Quantum Physics · Physics 2025-12-03 Xiaodie Lin , Haidong Yuan

By exploiting a generalization of recent results on environment-assisted channel correction, we show that, whenever a quantum system undergoes a channel realized as an interaction with a probe, the more efficiently the information about the…

Quantum Physics · Physics 2007-10-29 Francesco Buscemi

We study the Kimble-Braunstein continuous-variable quantum teleportation with the quantum channel physically realized in the turbulent atmosphere. In this context, we examine the applicability of different strategies preserving the Gaussian…

Quantum Physics · Physics 2019-09-27 K. Hofmann , A. A. Semenov , W. Vogel , Martin Bohmann

Quantum state purification is crucial in quantum communication and computation, aiming to recover a purified state from multiple copies of an unknown noisy state. This work introduces a general state purification framework designed to…

Quantum Physics · Physics 2024-09-27 Hongshun Yao , Yu-Ao Chen , Erdong Huang , Kaichu Chen , Honghao Fu , Xin Wang

If a quantum channel is commutable with a certain set of operators, a Choi state of the channel becomes a sufficient resource for any entanglement generation achieved by a single use of the channel with the help of local operation and…

Quantum Physics · Physics 2016-03-18 Ryo Namiki

We investigate prepare-and-measure scenarios in which a sender and a receiver use entanglement to send quantum information over a channel with limited capacity. We formalise this framework, identify its basic properties and provide…

Quantum Physics · Physics 2026-04-07 Elna Svegborn , Jef Pauwels , Armin Tavakoli

We study the use of entanglement purification for quantum communication over long distances. For distances much longer than the coherence length of a corresponding noisy quantum channel, the fidelity of transmission is usually so low that…

Quantum Physics · Physics 2008-12-18 W. Dür , H. - J. Briegel , J. I. Cirac , P. Zoller

In this review we discuss how channel simulation can be used to simplify the most general protocols of quantum parameter estimation, where unlimited entanglement and adaptive joint operations may be employed. Whenever the unknown parameter…

We propose a single auxiliary-assisted purification-based framework for quantum error correction, capable of correcting errors that drive a system from its ground-state subspace into excited-state sectors. The protocol consists of a joint…

Quantum Physics · Physics 2025-12-11 Chandrima B. Pushpan , Tanoy Kanti Konar , Aditi Sen De , Amit Kumar Pal

A noisy Gaussian channel is defined as a channel in which an input field mode is subjected to random Gaussian displacements in phase space. We introduce the quantum fidelity of a Gaussian channel for pure and mixed input states, and we…

Quantum Physics · Physics 2007-05-23 Carlton M. Caves , Krzysztof Wodkiewicz

Quantum state purification is the task of recovering a nearly pure copy of an unknown pure quantum state using multiple noisy copies of the state. This basic task has applications to quantum communication over noisy channels and quantum…

Quantum Physics · Physics 2025-01-22 Andrew M. Childs , Honghao Fu , Debbie Leung , Zhi Li , Maris Ozols , Vedang Vyas

Performance of quantum teleportation is typically measured by the average fidelity, an overlap between the input and output states. Along with the first moment, we introduce the second moment of fidelity in CV teleportation, i.e., the…

Quantum Physics · Physics 2022-09-16 Ayan Patra , Rivu Gupta , Saptarshi Roy , Aditi Sen De

The performance of a practical continuous-variable (CV) quantum key distribution (QKD) protocol depends significantly, apart from the loss and noise of the quantum channel, on the post-processing steps which lead to the extraction of the…

We show that the fidelity of the standard quantum teleportation protocol, which utilizes an impure resource state, applied successively, can be significantly improved, when used in conjunction with a quantum switch. In particular, we find…

Quantum Physics · Physics 2025-07-14 Chiranjib Mukhopadhyay , Arun Kumar Pati

In this paper we are interested to model quantum signal by statistical signal processing methods. The Gaussian distribution has been considered for the input quantum signal as Gaussian state have been proven to a type of important robust…

Quantum Physics · Physics 2023-02-17 Mouli Chakraborty , Harun Siljak , Indrakshi Dey , Nicola Marchetti

We investigate the continuous-variable entanglement swapping protocol in a non-Gaussian setting, with non- Gaussian states employed either as entangled inputs and/or as swapping resources. The quality of the swapping protocol is assessed in…

Quantum Physics · Physics 2021-10-26 F. Dell'Anno , D. Buono , G. Nocerino , S. De Siena , F. Illuminati

Long-distance optical quantum channels are necessarily lossy, leading to errors in transmitted quantum information, entanglement degradation and, ultimately, poor protocol performance. Quantum states carrying information in the channel can…

Quantum error mitigation is a key approach for extracting target state properties on state-of-the-art noisy machines and early fault-tolerant devices. Using the ideas from flag fault tolerance and virtual state purification, we develop the…

Quantum Physics · Physics 2025-03-31 Zhenhuan Liu , Xingjian Zhang , Yue-Yang Fei , Zhenyu Cai

We propose a new protocol of implementing continuous-variable quantum state transfer using partially disembodied transport. This protocol may improve the fidelity at the expense of the introduction of a semi-quantum channel between the…

Quantum Physics · Physics 2009-11-11 Jing Zhang , Changde Xie , Kunchi Peng

Time-varying quantum channels are essential for modeling realistic quantum systems with evolving noise properties. Here, we consider Gaussian lossy channels varying from one use to another and we employ neural networks to classify, regress,…