Nonlinear Tripartite Entangled State Representation and Related Generalized Wigner Function

We construct the nonlinear tripartite entangled state representation and the related generalized Wigner operator. Then we discussed the Wigner functions of the nonlinear tripartite entangled state and the three-mode nonlinear squeezed vacuum state, and obtained the classical Weyl corresponding function of the three-mode nonlinear squeezed state.

Tripartite Nonlinear Entangled State Representations in Quantum Mechanics

Based on the technique of integral within an ordered product of nonlinear bosonic operators we construct a kind of tripartite nonlinear entangled states, which can make up a complete set. As its application, we also derive nonlinear 3-mode charge-related entangled state. The essential point for constructing these states lies in choosing the appropriate charge operator.

Nonlinear Einstein-Podolsky-Rosen Entangled States

Using the properties of the inverses of annihilation and creation operators of f-oscillator we introduce the notion of nonlinear Einstein Podolsky-Rosen entangled state and study its properties.

Three-Mode Cyclic Squeezed States Constructed via EPR Entangled State

We construct the three-mode cyclic squeezed states and analyze its squeezing property by using the technique of integration within an ordered product of operators and the natural representation of the two-mode squeezing operator in the Einstein-Podolsky-Rosen entangled state basis.

Effects of Nonlinear Couplings on Entanglement in a Two-Qutrit Heisenberg XXX Chain under an Inhomogeneous Magnetic Field

This paper investigates the entanglement of a two-qutrit Heisenberg XXX chain with nonlinear couplings under an inhomogeneous magnetic field. By the concept of negativity, we find that the critical temperature increases with the increase of inhomogeneous magnetic field b. Our study indicates that for any ｜K｜ 〉 ｜J｜, or ｜K｜ 〈 ｜J｜ entanglement always exists for certain regions. We also find that at the critical point, the entanglement becomes a nonanalytic function of B and a quantum phase transition occurs.

New Tripartite Nonlinear Entangled State Representation in Quantum Mechanics

Based on the technique of integral within an ordered product of nonlinear bosonic operators,we constructa new kind of tripartite nonlinear entangled state |α,γ〉_λ in 3-mode Fock space,which can make up a complete set.Wealso simply discuss its properties and application.

Entanglement Dynamics of Atoms in Double Jaynes-Cummings Models with Kerr Medium

Entanglement dynamics of the atoms in the double Jaynes-Cummings models with the Kerr medium isstudied, and the effect of the Kerr medium on that is examined.The result shows that, the Kerr medium can control theentanglement dynamics of the atoms and repress entanglement sudden death.We can obtain the maximum entanglementbetween the atoms by strengthening the nonlinear interaction of the Kerr medium.

Heralded entanglement concentration for photon systems with linear-optical elements

We present two nonlocal entanglement concentration protocols(ECPs)to distill a subset of N-photon systems in a GreenbergerHorne-Zeilinger(GHZ)state or a W state from a set of photon systems in a partially entangled GHZ-like pure state or a lessentangled W-like state with known parameters,respectively.Our ECPs have some advantages.First,our ECPs work in a heralded way with linear-optical elements only,without the postselection based on nonlinear optics,far different from the previous ECPs.Second,they require only a copy of the less-entangled photon system in each round of the entanglement concentration process,not two copies,which decreases the difficulty of their implementation in experiment largely.Third,our ECPs avoid checking the photon number in the output modes of linear-optical elements with the sophisticated single-photon detectors.Moreover,all parties can operate the process for concentration simultaneously and independently,which leads to flexible operations and improves the performance greatly in experiment.These advantages make our ECPs useful in practical applications in long-distance quantum communication network.

Efcient Multipartite Polarization Entanglement Distribution Over Arbitrary Noise Channel

We present an efficient faithful multipartite polarization entanglement distribution protocol over an ar- bitrary noisy channel. The spatial degree of freedom is used to carry the entanglement during the transmission. We describe the principle by distributing n-qubit Greenberge-Horne--Zeilinger state and n-qubit W state. Our scheme can be used to distribute arbitrary n-qUbit entangled states to n distant locations. The remote parties can obtain maximally entangled states deterministically on the polarization of photons. Only passive linear optics are employed in our setup, which makes our scheme more feasible and efficient for practical application in long distance quantum communication.

Fast Generation of GHZ States with Bose–Einstein Condensate in a Cavity

It is shown that strong coupling of Bose-Einstein condensates to an optical cavity can be realized ex- perimentally. With an additional driven microwave field, we show that a highly nonlinear coupling among atoms in a Bose-Einstein condensate can be induced with the assistance of the cavity mode. With such interaction we can investigate the generation of many body entangled states. In particularly, we show that multipartite entangled CHZ states can be obtained in such architecture with current available techniques.