English
Related papers

Related papers: Detecting and quantifying entanglement on near-ter…

200 papers

The Variational Quantum Eigensolver (VQE) is a hybrid quantum-classical algorithm for preparing ground states in the current era of noisy devices. The classical component of the algorithm requires a large number of measurements on…

Quantum Physics · Physics 2025-03-27 Akib Karim , Shaobo Zhang , Muhammad Usman

The detection of entanglement provides a definitive proof of quantumness. Its ascertainment might be challenging for hot or macroscopic objects, where entanglement is typically weak, but nevertheless present. Here we propose a platform for…

Quantum Physics · Physics 2023-05-10 Tanjung Krisnanda , Tomasz Paterek , Mauro Paternostro , Timothy C. H. Liew

The quantification of the entanglement present in a physical system is of para\-mount importance for fundamental research and many cutting-edge applications. Currently, achieving this goal requires either a priori knowledge on the system or…

Variational quantum algorithms (VQAs), which classically optimize a parametrized quantum circuit to solve a computational task, promise to advance our understanding of quantum many-body systems and improve machine learning algorithms using…

Quantum Physics · Physics 2023-06-09 Roeland Wiersema , Cunlu Zhou , Juan Felipe Carrasquilla , Yong Baek Kim

Entanglement plays a central role in quantum information processing, indicating the non-local correlation of quantum matters. However, few effective ways are known to detect the amount of entanglement of an unknown quantum state. In this…

Quantum Physics · Physics 2020-11-26 You Zhou , Pei Zeng , Zhenhuan Liu

Quantum error correction is crucial for protecting quantum information against decoherence. Traditional codes like the surface code require substantial overhead, making them impractical for near-term, early fault-tolerant devices. We…

Quantum Physics · Physics 2026-04-13 Nico Meyer , Christopher Mutschler , Andreas Maier , Daniel D. Scherer

We propose to detect quantum entanglement by a condition of local measurments. We find that this condition can detect efficiently the pure entangled states for both discrete and continuous variable systems. It does not depend on…

Quantum Physics · Physics 2015-05-30 Qing Xie , X. -X. Wu , X. -M. Ding , W. -L. Yang , R. -H. Yue , H. Fan

Quantum networks (QNs) promise to enhance the performance of various quantum technologies in the near future by distributing entangled states over long distances. The first step towards this is to develop novel entanglement measures that…

Quantum Physics · Physics 2025-04-15 Yaqi Zhao , Jinchuan Hou , Kan He , Nicolò Lo Piparo , Xiangyi Meng

Paramount for performances of quantum network applications are the structure and quality of distributed entanglement. Here we propose a scalable and efficient approach to reveal the topological information of unknown quantum networks, and…

Quantum Physics · Physics 2025-07-15 Jun-Hao Wei , Xin-Yu Xu , Shu-Ming Hu , Nuo-Ya Yang , Li Li , Nai-Le Liu , Kai Chen

Quantum entanglement is a key resource in quantum computing and quantum information processing tasks. However, its quantification remains a major challenge since it cannot be directly extracted from physical observables. To address this…

Quantum Physics · Physics 2025-12-29 Shruti Aggarwal , Trasha Gupta , R. K. Agrawal , S. Indu

We propose a general method for introducing extensive characteristics of quantum entanglement. The method relies on polynomials of nilpotent raising operators that create entangled states acting on a reference vacuum state. By introducing…

Quantum Physics · Physics 2008-11-26 A. Mandilara , V. M. Akulin , A. V. Smilga , L. Viola

We present the variational separability verifier (VSV), which is a novel variational quantum algorithm (VQA) that determines the closest separable state (CSS) of an arbitrary quantum state with respect to the Hilbert-Schmidt distance (HSD).…

Quantum Physics · Physics 2022-12-20 Mirko Consiglio , Tony John George Apollaro , Marcin Wieśniak

Although the realization of useful quantum computers poses significant challenges, swift progress in emerging quantum technologies is making this goal realistically approachable. In this context, one of the essential resources is quantum…

Quantum Physics · Physics 2022-01-11 Valeria Saggio , Philip Walther

Quantum communication devices, such as quantum repeaters, quantum memories, or quantum channels, are unavoidably exposed to imperfections. However, the presence of imperfections can be tolerated, as long as we can verify such devices retain…

Quantum Physics · Physics 2011-05-26 Nathan Killoran , Norbert Lütkenhaus

Entropy plays a crucial role in both physics and information science, encompassing classical and quantum domains. In this work, we present the Quantum Neural Entropy Estimator (QNEE), a novel approach that combines classical neural network…

Quantum Physics · Physics 2023-12-19 Sangyun Lee , Hyukjoon Kwon , Jae Sung Lee

A major challenge in quantum information is characterizing entanglement, for which entanglement witnesses offer effective means of detecting quantum correlations. We introduce a hybrid quantum-classical framework that learns a nonlinear…

Quantum Physics · Physics 2025-09-09 Mohammad Rezaei Shokou , Hossein Davoodi Yeganeh

Entanglement constitutes a key characteristic feature of quantum matter. Its detection, however, still faces major challenges. In this letter, we formulate a framework for probing entanglement based on machine learning techniques. The…

Quantum Physics · Physics 2021-08-18 Jun Yong Khoo , Markus Heyl

Entanglement is known to significantly improve the performance (separately) of communication and detection schemes that utilize quantum resources. This work explores the simultaneous utility of quantum entanglement for (joint) communication…

Quantum Physics · Physics 2025-10-22 Yuhang Yao , Syed A. Jafar

Quantifying quantum mechanical uncertainty is vital for the increasing number of experiments that reach the uncertainty limited regime. We present a method for computing tight variance uncertainty relations, i.e., the optimal…

Quantum Physics · Physics 2017-11-01 René Schwonnek , Lars Dammeier , Reinhard F. Werner

Discrete-variable (DV) entanglement is crucial for numerous quantum applications, yet its deterministic generation in many bosonic systems remains experimentally challenging. In contrast, continuous-variable (CV) entanglement can be…

Quantum Physics · Physics 2026-03-16 Pak-Tik Fong , Ruchir Tullu , Hoi-Kwan Lau