Entanglement properties of multi-cascaded beamsplitter and its applications

Based on the Weyl expansion representation of Wigner operator and its invariant property under similar transformation, we derived the relationship between input state and output state after a unitary transformation including Wigner function and density operator. It is shown that they can be related by a transformation matrix corresponding to the unitary evolution. In addition, for any density operator going through a dissipative channel, the evolution formula of the Wigner function is also derived. As applications, we considered further the two-mode squeezed vacuum as inputs, and obtained the resulted Wigner function and density operator within normal ordering form. Our method is clear and concise, and can be easily extended to deal with other problems involved in quantum metrology, steering, and quantum information with continuous variable.

Section: Discussionmentioning

confidence: 97%

Evolution of quantum states via Weyl expansion in dissipative channel*

Rao

Kuang

2019

“…Quantum entanglement is one of the interesting physical properties of quantum mechanics and has been widely studied. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] By using prior shared entanglement and classical communication, Alice can send Bob who locates remotely an unknown quantum state without actually sending the particle using quantum teleportation. [15] Quantum teleportation has wide applications in quantum communication and quantum computing.…”

Section: Introductionmentioning

confidence: 99%

Quantum teleportation of particles in an environment*

Liu

2020

We discuss the teleportation of particles in an environment of an N-body system. In this case, we can change a many-body system into an arbitrary shape in space by teleporting some or all the constituent particles, and thus we call the quantum teleportation under this circumstance as quantum tele-transformation (QTT). The particular feature of QTT is that the wave function of the internal degrees of freedom remains the same, while the spatial wave function experiences a drastic change. The notion of QTT provides conceptual and pedagogical convenience for quantum information processing. In view of QTT, teleportation is the change of a single particle in space, while entanglement swapping is the change of one particle of an entangled pair.

“…Entanglement is considered as the central resource for quantum information and computation, [1][2][3][4] and numerous theoretical and experimental researches have been conducted in this field. [5][6][7][8] In particular, the search for maximally entangled states has received a great deal of attention.…”

Section: Introductionmentioning

confidence: 99%

Relations between tangle and I concurrence for even n-qubit states

Zha

Miao

2019

Gilad Gour and Nolan R Wallach [J. Math. Phys. 51 112201 (2010)] have proposed the 4-tangle and the square of the I concurrence. They also gave the relationship between the 4-tangle and the square of the I concurrence. In this paper, we give the expression of the square of the I concurrence and the n-tangle for six-qubit and eight-qubit by some local unitary transformation invariant. We prove that in six-qubit and eight-qubit states there exist strict monogamy laws for quantum correlations. We elucidate the relations between the square of the I concurrence and the n-tangle for six-qubit and eight-qubits. Especially, using this conclusion, we can show that 4-uniform states do not exist for eight-qubit states.