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Related papers: Verification of quantum discord

200 papers

A proof of quantumness (PoQ) allows a classical verifier to efficiently test if a quantum machine is performing a computation that is infeasible for any classical machine. In this work, we propose a new approach for constructing PoQ…

Quantum Physics · Physics 2025-06-02 Giulio Malavolta , Tamer Mour

Quantum discord witnesses the nonclassicality of quantum states even when there is no entanglement in these quantum states. This type of quantum correlation also has some interesting and significant applications in quantum information…

Quantum Physics · Physics 2015-05-19 Mazhar Ali

Quantum discord in a bipartite system can be dynamically revealed and quantified through purely local operations on one of the two subsystems. To achieve this, the local detection method harnesses the influence of initial correlations on…

Quantum Physics · Physics 2017-07-04 Manuel Gessner , Heinz-Peter Breuer , Andreas Buchleitner

We describe and realize an experimental procedure for assessing the incompatibility of two qubit measurements. The experiment consists in a state discrimination task where either measurement is used according to some partial intermediate…

Quantum computers are on the brink of surpassing the capabilities of even the most powerful classical computers. This naturally raises the question of how one can trust the results of a quantum computer when they cannot be compared to…

Two geometric measures for quantum discord were recently proposed by Modi et al. [Phys. Rev. Lett. 104, 080501 (2010)] and Dakic et al. [Phys. Rev. Lett. 105, 190502 (2010)]. We study the similarities and differences for total quantum…

Quantum Physics · Physics 2011-09-09 Zhenyu Xu , Wanli Yang , Xing Xiao , Mang Feng

We evaluate analytically the quantum discord for a large family of multiqubit states. It is interesting to note that the quantum discord of three-qubits and five-qubits is the same, as is the quantum discord of two-qubits and six-qubits. We…

Quantum Physics · Physics 2021-08-04 Bo Li , Chen-Lu Zhu , Xiao-Bin Liang , Biao-Liang Ye , Shao-Ming Fei

We studied the geometric quantum discord of a quantum system consisted of a Jaynes- Cummings atom, a cavity and an isolated atom. The analytical expressions of the geometric quantum discord for two atoms, every atom with cavity and the…

Quantum Physics · Physics 2015-05-01 Wen-Chao Qiang , Lei Zhang , Hua-Ping Zhang

The minimal Bures distance of a quantum state of a bipartite system AB to the set of classical states for subsystem A defines a geometric measure of quantum discord. When A is a qubit, we show that this geometric quantum discord is given in…

Quantum Physics · Physics 2013-12-24 Dominique Spehner , Miguel Orszag

Intermediate-scale quantum devices are becoming more reliable, and may soon be harnessed to solve useful computational tasks. At the same time, common classical methods used to verify their computational output become intractable due to a…

Quantum Physics · Physics 2023-07-03 Johannes Knörzer , Daniel Malz , J. Ignacio Cirac

Quantum incompatibility, referred as the phenomenon that some quantum measurements cannot be performed simultaneously, is necessary for various quantum information processing tasks, such as nonlocality and steering. When these applications…

Quantum Physics · Physics 2024-11-19 Xiaolin Zhang , Rui Qu , Zehong Chang , Yunlong Wang , Zhenyu Guo , Min An , Hong Gao , Fuli Li , Pei Zhang

The presence of noise in quantum computers hinders their effective operation. Even though quantum error correction can theoretically remedy this problem, its practical realization is still a challenge. Testing and benchmarking noisy,…

Quantum Physics · Physics 2023-02-15 Adrian Ortega , Orsolya Kálmán , Tamás Kiss

Many existing genuine multipartite entanglement (GME) witnesses for continuous-variable (CV) quantum systems typically rely on quadrature measurements, which is challenging to implement in platforms where the CV degrees of freedom can be…

Quantum Physics · Physics 2025-10-31 Lin Htoo Zaw , Jiajie Guo , Qiongyi He , Shuheng Liu , Matteo Fadel

We present a method to test quantum behavior of quantum information processing devices, such as quantum memories, teleportation devices, channels and quantum key distribution protocols. The test of quantum behavior can be phrased as the…

Quantum Physics · Physics 2008-03-07 Hauke Häseler , Tobias Moroder , Norbert Lütkenhaus

We study the dynamics of geometric measure of quantum discord (GMQD) under the influences of two local phase damping noises. Consider the two qubits initially in arbitrary X-states, we find the necessary and sufficient conditions for which…

Quantum Physics · Physics 2015-10-20 Wei Song , Zhuo-Liang Cao

Two-qubit X-state is a large class of quantum states which plays an important role in the quantification and dynamical study of quantum correlations. However, the corresponding quantification of quantum discord is still missing for bona…

Quantum Physics · Physics 2021-06-23 Chunhe Xiong , Guijun Zhang

The problem of recognizing (non-)Markovianity of a quantum dynamics is revisited through analyzing quantum correlations. We argue that instantaneously-vanishing quantum discord provides a necessary and sufficient condition for Markovianity…

Quantum Physics · Physics 2012-05-21 S. Alipour , A. Mani , A. T. Rezakhani

Quantum discord quantifies quantum correlations beyond entanglement and assumes nonzero values, which are notoriously hard to compute, for almost all quantum states. Here we provide computable tight bounds for the quantum discord for…

Quantum Physics · Physics 2011-03-01 Sixia Yu , Chengjie Zhang , Qing Chen , C. H. Oh

Quantum coherence is the most fundamental of all quantum quantifiers, underlying other well-known quantities such as entanglement, quantum discord, and Bell correlations. It can be distributed in a multipartite system in various ways -- for…

In this work we investigate how to quantify the coherence of quantum measurements. First, we establish a resource theoretical framework to address the coherence of measurement and show that any statistical distance can be adopted to define…

Quantum Physics · Physics 2020-08-11 Kyunghyun Baek , Adel Sohbi , Jaehak Lee , Jaewan Kim , Hyunchul Nha