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Related papers: Maximizing the entanglement of two mixed qubits

200 papers

We consider entanglement for quantum states defined in vector spaces over the real numbers. Such real entanglement is different from entanglement in standard quantum mechanics over the complex numbers. The differences provide insight into…

Quantum Physics · Physics 2007-05-23 Carlton M. Caves , Christopher A. Fuchs , Pranaw Rungta

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 propose a detailed study of the geometric entanglement properties of pure symmetric N-qubit states, focusing more particularly on the identification of symmetric states with a high geometric entanglement and how their entanglement…

Quantum Physics · Physics 2010-07-01 J. Martin , O. Giraud , P. A. Braun , D. Braun , T. Bastin

Maximally entangled states are of utmost importance to quantum communication, dense coding, and quantum teleportation. With a trapped ion placed inside a high finesse optical cavity, interacting with field of an external laser and quantized…

Quantum Physics · Physics 2009-11-11 S. Shelly Sharma , N. K. Sharma

We present a new method of analytically deriving the entanglement of formation of the bipartite mixed state. The method realizes the optimal decomposition families of states. Our method can lead to many new results concerning entanglement…

Quantum Physics · Physics 2007-10-16 Lin Chen , Yi-Xin Chen

We first present a generalized criterion for maximally entangled states of 2, 3, 4, 5, 6, 8 and in theory to arbitrary-number qubits. By this criterion, some known highly entangled multi-qubit states are examined and a new genuine…

Quantum Physics · Physics 2015-06-04 Xinwei Zha , Chenzhi Yuan , Yanpeng Zhang

We analyze tight informationally complete measurements for arbitrarily large multipartite systems and study their configurations of entanglement. We demonstrate that tight measurements cannot be exclusively composed neither of fully…

Quantum Physics · Physics 2018-06-26 Jakub Czartowski , Dardo Goyeneche , Karol Życzkowski

We analyze various scenarios for entangling two initially unentangled qubits. In particular, we propose an optimal universal entangler which entangles a qubit in unknown state $|\Psi>$ with a qubit in a reference (known) state $|0>$. That…

Quantum Physics · Physics 2009-11-06 Vladimir Buzek , Mark Hillery

The ability to teleport entanglement through maximally entangled mixed states as defined by concurrence and linear entropy is studied. We show how the teleported entanglement depends on the quality of the quantum channel used, as defined…

Quantum Physics · Physics 2017-10-03 S. Campbell , M. Paternostro

Entanglement and steering are used to describe quantum inseparabilities. Steerable states form a strict subset of entangled states. A natural question arises concerning how much territory steerability occupies entanglement for a general…

Quantum Physics · Physics 2021-09-01 Xiao-Gang Fan , Huan Yang , Fei Ming , Zhi-Yong Ding , Dong Wang , Liu Ye

We analytically obtain the maximum probability of converting a finite number of copies of an arbitrary two-qubit pure state to a single copy of a maximally entangled two-qubit pure state via entanglement assisted local operations and…

Quantum Physics · Physics 2020-07-22 Siddhartha Santra , Vladimir S. Malinovsky

The Schmidt coefficients capture all entanglement properties of a pure bipartite state and therefore determine its usefulness for quantum information processing. While the quantification of the corresponding properties in mixed states is…

Quantum Physics · Physics 2019-04-08 Gael Sentís , Christopher Eltschka , Otfried Gühne , Marcus Huber , Jens Siewert

The monogamy of entanglement means that entanglement cannot be freely shared. In 2014, Oliveira et al. [ Oliveira et al., Phys. Rev. A. 89, 034303 (2014)] proposed a monogamy relation in the linear version and considered it in terms of…

Quantum Physics · Physics 2021-08-04 Xian Shi , Lin Chen , Mengyao Hu

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement, already present in a number of settings (see Shimony 1995 and…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Paul M. Goldbart

Following the recent work of Caves, Fuchs, and Rungta [Found. of Phys. Lett. {\bf 14} (2001) 199], we discuss some entanglement properties of two-rebits systems. We pay particular attention to the relationship between entanglement and…

Quantum Physics · Physics 2015-06-26 J. Batle , A. R. Plastino , M. Casas , A. Plastino

The unambiguous detection and quantification of entanglement is a hot topic of scientific research, though it is limited to low dimensions or specific classes of states. Here we identify an additional class of quantum states, for which…

Quantum Physics · Physics 2014-12-03 Marco Roncaglia , Arianna Montorsi , Marco Genovese

Nonlocality and quantum entanglement constitute two special aspects of the quantum correlations existing in quantum systems, which are of paramount importance in quantum-information theory. Traditionally, they have been regarded as…

Quantum Physics · Physics 2015-05-27 J. Batle , M. Casas

A complete analysis of entangled bipartite qutrit pure states is carried out based on a simple entanglement measure. An analysis of all possible extremally entangled pure bipartite qutrit states is shown to reduce, with the help of SLOCC…

Quantum Physics · Physics 2009-11-11 Feng Pan , Guoying Lu , J. P. Draayer

We show that two identical solid-state qubits can be made fully entangled (starting from completely mixed state) with probability 1/4 just measuring them by a detector, equally coupled to the qubits. This happens in the case of repeated…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Rusko Ruskov , Alexander N. Korotkov

Quantifying mixed-state entanglement in many-body systems has been a formidable task. In this work, we quantify the entanglement of states in unresolvable spin ensembles, which are inherently mixed. By exploiting their permutationally…

Quantum Physics · Physics 2025-11-05 Tzu-Wei Kuo , Hoi-Kwan Lau