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Related papers: Maximal Magic for Two-qubit States

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Motivated by M\"obius transformation for symmetrical points under the generalized circle in complex plane, the system of symmetrical spin coherent states corresponding to antipodal qubit states is introduced. It implies the maximally…

Quantum Physics · Physics 2011-07-08 Oktay Pashaev , Zeynep Nilhan Gurkan

In this paper, we find the necessary and sufficient condition for the maximal entanglement of the state, $ |\psi>=\mu|\alpha>|\beta>+\lambda|\alpha>|\delta>+ \rho|\gamma>|\beta>+\nu|\gamma>|\delta>,$ constructed by linearly independent…

Quantum Physics · Physics 2011-04-28 G. Najarbashi , Y. Maleki

We investigate the possibility of simulating partially entangled two qubit states by separable states of higher spins. First, we show that all partially entangled isotropic states can be simulated classically. We further investigate…

Quantum Physics · Physics 2014-01-23 H. M. Bharath , V. Ravishankar

We discuss the problem of characterizing upper bounds on entanglement in a bipartite quantum system when only the reduced density matrices (marginals) are known. In particular, starting from the known two-qubit case, we propose a family of…

Local Markovian noise cannot bring entanglement back, but it can bring magic back. Unlike separability, stabilizer membership is not preserved by local channels, allowing dissipation to push states out of the stabilizer polytope as well as…

Quantum Physics · Physics 2026-05-22 Chenfeng Cao

Understanding quantum magic (i.e., nonstabilizerness) in many-body quantum systems is challenging but essential to the study of quantum computation and many-body physics. We investigate how noise affects magic properties in entangled…

Quantum Physics · Physics 2024-10-29 Fuchuan Wei , Zi-Wen Liu

To date all self-tests for high dimensional systems are confined to many-qubit states. This is due to two restrictions in the literature: the standard techniques for proving self-testing results apply only to qubits, and there are few…

Quantum Physics · Physics 2016-08-18 Matthew McKague

We study the fully entangled fraction of quantum states. An upper bound is obtained for arbitrary dimensional bipartite systems. This bound is shown to be exact for the case of two-qubit systems. An inequality related the fully entangled…

Quantum Physics · Physics 2009-11-13 Ming Li , Shao-Ming Fei , Zhi-Xi Wang

How entangled is a randomly chosen bipartite stabilizer state? We show that if the number of qubits each party holds is large the state will be close to maximally entangled with probability exponentially close to one. We provide a similar…

Quantum Physics · Physics 2007-05-23 Graeme Smith , Debbie Leung

Magic states are key ingredients in schemes to realize universal fault-tolerant quantum computation. Theories of magic states attempt to quantify this computational element via monotones and determine how these states may be efficiently…

Quantum Physics · Physics 2022-04-28 Nikolaos Koukoulekidis , David Jennings

Recently, the fast development of quantum technologies led to the need for tools allowing the characterization of quantum resources. In particular, the ability to estimate non-classical aspects, e.g. entanglement and quantum discord, in…

We propose families of protocols for magic state distillation -- important components of fault tolerance schemes --- for systems of odd prime dimension. Our protocols utilize quantum Reed-Muller codes with transversal non-Clifford gates. We…

Quantum Physics · Physics 2013-01-01 Earl T. Campbell , Hussain Anwar , Dan E. Browne

We revisit the relationship between quantum separability and the sign of the relative q-entropies of composite quantum systems. The q-entropies depend on the density matrix eigenvalues p_i through the quantity omega_q = sum_i p_i^q. Renyi's…

Quantum Physics · Physics 2016-09-08 J. Batle , A. R. Plastino , M. Casas , A. Plastino

We report an exhaustive numerical analysis of violations of local realism by two qutrits in all possible pure entangled states. In Bell type experiments we allow any pairs of local unitary U(3) transformations to define the measurement…

Quantum Physics · Physics 2015-06-03 Jacek Gruca , Wieslaw Laskowski , Marek Zukowski

We advance the characterization of complexity in quantum many-body systems by examining $W$-states embedded in a spin chain. Such states show an amount of non-stabilizerness or "magic" (measured as the Stabilizer R\'enyi Entropy -SRE-) that…

Quantum Physics · Physics 2026-01-30 J. Odavić , T. Haug , G. Torre , A. Hamma , F. Franchini , S. M. Giampaolo

We consider a two-qubit unitary operation along with arbitrary local unitary operations acts on a two-qubit pure state, whose entanglement is C_0. We give the conditions that the final state can be maximally entangled and be non-entangled.…

Quantum Physics · Physics 2009-11-10 M. -Y. Ye , Dong Sun , Y. -S. Zhang , G. -C. Guo

While it has recently been demonstrated how to certify the maximal amount of randomness from any pure two-qubit entangled state in a device-independent way [E. Woodhead et al., Phys. Rev. Research 2, 042028(R)(2020)], the problem of optimal…

Entanglement and Bell nonlocality are used to describe quantum inseparabilities. Bell-nonlocal states form a strict subset of entangled states. A natural question arises concerning how much territory Bell nonlocality occupies entanglement…

Quantum Physics · Physics 2019-09-04 Xiao-Gang Fan , Zhi-Yong Ding , Fei Ming , Huan Yang , Dong Wang , Liu Ye

We present the modified relative entropy of entanglement (MRE) in order to both improve the computability for the relative entropy of entanglement and avoid the problem that the entanglement of formation seems to be greater than…

Quantum Physics · Physics 2007-05-23 An Min Wang

To run large-scale algorithms on a quantum computer, error-correcting codes must be able to perform a fundamental set of operations, called logic gates, while isolating the encoded information from…