English
Related papers

Related papers: Classicality witness for two-qubit states

200 papers

The machinery of qubit-portraits of qudit states, recently presented, is consider here in more details in order to characterize the presence of quantum correlations in bipartite qudit states. In the tomographic representation of quantum…

Quantum Physics · Physics 2008-11-26 C. Lupo , V. I. Man'ko , G. Marmo

We examine the possible states of subsystems of a system of bits or qubits. In the classical case (bits), this means the possible marginal distributions of a probability distribution on a finite number of binary variables; we give necessary…

Quantum Physics · Physics 2015-06-26 Paul Butterley , Anthony Sudbery , Jason Szulc

We present a classical interactive protocol that verifies the validity of a quantum witness state for the local Hamiltonian problem. It follows from this protocol that approximating the non-local value of a multi-player one-round game to…

Quantum Physics · Physics 2015-05-28 Zhengfeng Ji

Simultaneous existence of correlation in complementary bases is a fundamental feature of quantum correlation, and we show that this characteristic is present in any non-product bipartite state. We propose a measure via mutually unbiased…

Quantum Physics · Physics 2014-12-08 Yu Guo , Shengjun Wu

Non-classical probability (along with its underlying logic) is a defining feature of quantum mechanics. A formulation that incorporates them, inherently and directly, would promise a unified description of seemingly different prescriptions…

Quantum Physics · Physics 2019-05-21 Soumik Adhikary , Sooryansh Asthana , V. Ravishankar

Quantum steering, measurement incompatibility, and instrument incompatibility have recently been recognized as unified manifestations of quantum incompatibility. Building on this perspective, we develop a general framework for constructing…

Quantum Physics · Physics 2026-01-06 Kuan-Yi Lee , Jhen-Dong Lin , Adam Miranowicz , Yueh-Nan Chen

We investigate the Peres-Horodecki positive partial transpose (PPT) criterion in the context of conserved quantities and derive a condition of in- separability for a composite bipartite system depending only on the dimen- sions of its…

Quantum Physics · Physics 2016-12-21 Ashutosh K. Goswami , Prasanta K. Panigrahi

We study the nonlocality of arbitrary dimensional bipartite quantum states. By computing the maximal violation of a set of multi-setting Bell inequalities, an analytical and computable lower bound has been derived for general two-qubit…

Quantum Physics · Physics 2015-09-04 Ming Li , Tinggui Zhang , Bobo Hua , Shao-Ming Fei , Xianqing Li-Jost

Experimental realization of various quantum states of interest has become possible in the recent past due to the rapid developments in the field of quantum state engineering. Nonclassical properties of such states have led to various…

Quantum Physics · Physics 2022-06-07 Kathakali Mandal , Nasir Alam , Amit Verma , Anirban Pathak , J. Banerji

We identify ambiguities in the available frameworks for defining quantum, classical, and total correlations as measured by discordlike quantifiers. More specifically, we determine situations for which either classical or quantum…

Quantum Physics · Physics 2014-12-10 F. M. Paula , A. Saguia , Thiago R. de Oliveira , M. S. Sarandy

We construct both nonlinear and linear entanglement witnesses, by tensoring and partial tracing existing states and witnesses. We show that little shared quantum resources allow to employ decomposable witnesses to obtain larger ones…

Quantum Physics · Physics 2025-11-11 Albert Rico

We consistently formalize the probabilistic description of multipartite joint measurements performed on systems of any nature. This allows us: (1) to specify in probabilistic terms the difference between nonsignaling, the Einstein-…

Quantum Physics · Physics 2010-12-20 Elena R. Loubenets

We present a class of linear correlation witnesses that detects bound entanglement within a three-party prepare-and-measure scenario with four-dimensional quantum messages. We relate the detection power of our witnesses for two-ququart…

Quantum Physics · Physics 2025-10-31 István Márton , Erika Bene , Tamás Vértesi

The state disturbance induced by locally measuring a quantum system yields a signature of nonclassical correlations beyond entanglement. Here we present a detailed study of such correlations for two-qubit mixed states. To overcome the…

Quantum Physics · Physics 2011-08-22 Davide Girolami , Mauro Paternostro , Gerardo Adesso

We propose a device-independent null witness dimensionality test with bipartite measurements and input from two separate parties. The dimension is determined from the rank of the matrix of measurements for pairs of states prepared by the…

Quantum Physics · Physics 2025-12-15 Josep Batle , Tomasz Białecki , Tomasz Rybotycki , Adam Bednorz

We consider multipartite quantum state discrimination and show that the minimum-error discrimination by separable measurements is closely related to the concept of entanglement witness. Based on the properties of entanglement witness, we…

Quantum Physics · Physics 2023-04-25 Donghoon Ha , Jeong San Kim

We study by comparison the structure of singlet type states in Q-bit space in the light of quantum and classical paradigms. It is shown that only the classical paradigm implies a variation in the visibility of correlation coefficients, that…

Quantum Physics · Physics 2007-05-23 A. F. Kracklauer

The characterization of quantum correlations in terms of information-theoretic resource has been a fruitful approach to understand the power of quantum correlations as a resource. While bipartite entanglement and Bell inequality violation…

Quantum Physics · Physics 2014-11-27 Florian Curchod , Yeong-Cherng Liang , Nicolas Gisin

We present a method to derive Bell monogamy relations by connecting the complementarity principle with quantum non-locality. The resulting monogamy relations are stronger than those obtained from the no-signaling principle alone. In many…

Quantum Physics · Physics 2013-05-29 P. Kurzynski , T. Paterek , R. Ramanathan , W. Laskowski , D. Kaszlikowski

We construct a set of 2^(2^n) independent Bell correlation inequalities for n-partite systems with two dichotomic observables each, which is complete in the sense that the inequalities are satisfied if and only if the correlations…

Quantum Physics · Physics 2009-11-07 R. F. Werner , M. M. Wolf