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A class of quantum protocols to teleport bipartite (entangled) states of two qubits is suggested. Our schemes require a single entangled pair shared by the two parties and the transmission of three bits of classical information, as well as…

Quantum Physics · Physics 2009-11-11 Mary M. Cola , Matteo G. A. Paris

Entanglement is one of the key resources required for quantum computation, so experimentally creating and measuring entangled states is of crucial importance in the various physical implementations of a quantum computer. In superconducting…

We consider the phase space for a system of $n$ identical qudits (each one of dimension $d$, with $d$ a primer number) as a grid of $d^{n} \times d^{n}$ points and use the finite field $GF(d^{n})$ to label the corresponding axes. The…

Quantum Physics · Physics 2009-10-29 A. B. Klimov , C. Munoz , L. L. Sanchez-Soto

This is a review of the geometry of quantum states using elementary methods and pictures. Quantum states are represented by a convex body, often in high dimensions. In the case of n-qubits, the dimension is exponentially large in n. The…

Quantum Physics · Physics 2019-08-12 Joseph Avron , Oded Kenneth

We define and study the properties of ``squeezed quantum multiplets''. Ordinary multiplets are sets of $D$-orthonormal quantum states formed by superpositions of states squeezed along $D$ equally spaced directions in quadrature space. More…

Quantum Physics · Physics 2025-12-25 Juan Pablo Paz , Corina Révora , Christian Tomás Schmiegelow

The concept of entanglement splitting is introduced by asking whether it is possible for a party possessing half of a pure bipartite quantum state to transfer some of his entanglement with the other party to a third party. We describe the…

Quantum Physics · Physics 2009-10-31 Dagmar Bruss

Magic, a key quantum resource beyond entanglement, remains poorly understood in terms of its structure and classification. In this paper, we demonstrate a striking connection between high-dimensional symmetric lattices and quantum magic…

Quantum Physics · Physics 2025-06-16 Misaki Ohta , Kazuki Sakurai

Genuine entanglement is the strongest form of multipartite entanglement. Genuinely entangled pure states contain entanglement in every bipartition and as such can be regarded as a valuable resource in the protocols of quantum information…

Quantum Physics · Physics 2021-12-07 K. V. Antipin

We discuss the relation between fermion entanglement and bipartite entanglement. We first show that an exact correspondence between them arises when the states are constrained to have a definite local number parity. Moreover, for arbitrary…

Quantum Physics · Physics 2017-06-21 N. Gigena , R. Rossignoli

We give a general solution to the question when the convex hulls of orbits of quantum states on a finite-dimensional Hilbert space under unitary actions of a compact group have a non-empty interior in the surrounding space of all density…

Mathematical Physics · Physics 2015-06-16 Janusz Grabowski , Alberto Ibort , Marek Kuś , Giuseppe Marmo

We consider the separability of various joint states for N qutrits. We derive two results: (i) the separability condition for a two-qutrit state that is a mixture of the maximally mixed state and a maximally entangled state (such a state is…

Quantum Physics · Physics 2009-10-31 Carlton M. Caves , Gerard J. Milburn

The present work studies quantum and classical correlations in three qubits and four qubits general Bell states, produced by operating with braid operators on the computational basis of states. The analogies between the general three qubits…

Quantum Physics · Physics 2014-11-12 Yacob Ben-Aryeh

We report an experiment to generate maximally entangled states of D-dimensional quantum systems, qudits, by using transverse spatial correlations of two parametric down-converted photons. Apertures with D-slits in the arms of the twin…

Quantum Physics · Physics 2009-11-10 Leonardo Neves , G. Lima , J. G. Aguirre Gómez , C. H. Monken , C. Saavedra , S. Pádua

Bell's states are among the most useful in quantum computing. These state are an orthonormal base of entagled states with two qubits. We propose alternative bases of entangled states. Some of these states depend on a continuous parameter.…

Quantum Physics · Physics 2025-05-28 Juan M. Romero , Emiliano Montoya-Gonzalez , Oscar Velazquez-Alvarado

We consider a quantum system with a finite number of distinguishable quantum states, which may be partitioned freely by a number of quantum particles, assumed to be maximally entangled. We show that if we partition the system into a number…

Discrete structures in Hilbert space play a crucial role in finding optimal schemes for quantum measurements. We solve the problem whether a complete set of five iso-entangled mutually unbiased bases exists in dimension four, providing an…

Quantum Physics · Physics 2020-03-10 Jakub Czartowski , Dardo Goyeneche , Markus Grassl , Karol Życzkowski

When a superposition $(|\alpha>-|-\alpha>)$ of two coherent states with opposite phase falls upon a 50-50 beamsplitter, the resulting state is entangled. Remarkably, the amount of entanglement is exactly 1 ebit, irrespective of $\alpha$, as…

Quantum Physics · Physics 2009-11-06 S. J. van Enk , O. Hirota

New convenient thumbrules are obtained to test entanglement of wavefunctions for bipartite qubit and qutrit systems. All results are analytic. The new results are: (a) For bipartite qubit systems there exists a matrix $A$ for which $\det A…

Quantum Physics · Physics 2025-05-28 Prabal Dasgupta , Debashis Gangopadhyay

The determination of genuine entanglement is a central problem in quantum information processing. We investigate the tripartite state as the tensor product of two bipartite entangled states by merging two systems. We show that the…

Quantum Physics · Physics 2021-02-03 Yize Sun , Lin Chen

A simple algebraic approach to the study of multipartite entanglement for pure states is introduced together with a class of suitable functionals able to detect entanglement. On this basis, some known results are reproduced. Indeed, by…

Quantum Physics · Physics 2013-07-17 S. Di Martino , B. Militello , A. Messina