Entropy product measure for multipartite pure states

The time evolution of the field quantum entropy and entanglement in a system of multi-mode coherent light field resonantly interacting with a two-level atom by degenerating the multi-photon process is studied by utilizing the Von Neumann reduced entropy theory, and the analytical expressions of the quantum entropy of the multimode field and the numerical calculation results for three-mode field interacting with the atom are obtained. Our attention focuses on the discussion of the influences of the initial average photon number, the atomic distribution angle and the phase angle of the atom dipole on the evolution of the quantum field entropy and entanglement. The results obtained from the numerical calculation indicate that: the stronger the quantum field is, the weaker the entanglement between the quantum field and the atom will be, and when the field is strong enough, the two subsystems may be in a disentangled state all the time; the quantum field entropy is strongly dependent on the atomic distribution angle, namely, the quantum field and the two-level atom are always in the entangled state, and are nearly stable at maximum entanglement after a short time of vibration; the larger the atomic distribution angle is, the shorter the time for the field quantum entropy to evolve its maximum value is; the phase angles of the atom dipole almost have no influences on the entanglement between the quantum field and the two-level atom. Entangled states or pure states based on these properties of the field quantum entropy can be prepared.field quantum entropy, Von Neumann reduced entropy, degenerate multi-photon process, quantum entanglement LIU WangYun et al.

Section: Introductionmentioning

confidence: 99%

Evolution of the field quantum entropy and entanglement in a system of multimode light field interacting resonantly with a two-level atom through N j -degenerate N Σ-photon process

Liu

Yang

2008

“…Refs. [15][16][17] [19] constructed another kind of two-mode coherent state, which is called the coherent-entangled state , , x α so named as it is the common eigenvector of 1 2( ) a a − and 1 2( )/2, x x + …”

mentioning

confidence: 99%

Generalized two-mode coherent-entangled state with real parameters

et al. 2009

The coherent-entangled state |α, x; λ> with real parameters λ is proposed in the two-mode Fock space, which exhibits the properties of both the coherent and entangled states. The completeness relation of |α, x; λ> is proved by virtue of the technique of integral within an ordered product of operators. The corresponding squeezing operator is derived, with its own squeezing properties. Furthermore, generalized P-representation in the coherent-entangled state is constructed. Finally, it is revealed that superposition of the coherent-entangled states may produce the EPR entangled state.bipartite coherent-entangled state, IWOP technique, classical transformation

“…The first scheme is based on the Bell-basis measurements and the receiver may probabilistically reconstruct the original state by performing proper transformation on her particles and an auxiliary two-level particle; the second scheme is based on the generalized Bell-basis measurements and the probability of successfully teleporting the unknown state depends on those measurements which are adjusted by Alice. A comparison of the two schemes shows that the latter has a smaller probability than that of the former and contrary to the former, the channel information and auxiliary qubit are not necessary for the receiver in the latter.quantum teleportation, qudit cluster state, generalized Bell-basis Quantum entanglement [1][2][3] , which has no classical analog, is one of the most notable features of quantum mechanics. It supplies many interesting applications in the field of information and the quantum teleportation is one of them.…”

mentioning

confidence: 99%

“…quantum teleportation, qudit cluster state, generalized Bell-basis Quantum entanglement [1][2][3] , which has no classical analog, is one of the most notable features of quantum mechanics. It supplies many interesting applications in the field of information and the quantum teleportation is one of them.…”

mentioning

confidence: 99%

Teleportation of an arbitrary two-qudit state based on the non-maximally four-qudit cluster state

Tian

Tao

Qin

2008

Two different schemes are presented for quantum teleportation of an arbitrary two-qudit state using a non-maximally four-qudit cluster state as the quantum channel. The first scheme is based on the Bell-basis measurements and the receiver may probabilistically reconstruct the original state by performing proper transformation on her particles and an auxiliary two-level particle; the second scheme is based on the generalized Bell-basis measurements and the probability of successfully teleporting the unknown state depends on those measurements which are adjusted by Alice. A comparison of the two schemes shows that the latter has a smaller probability than that of the former and contrary to the former, the channel information and auxiliary qubit are not necessary for the receiver in the latter.quantum teleportation, qudit cluster state, generalized Bell-basis Quantum entanglement [1][2][3] , which has no classical analog, is one of the most notable features of quantum mechanics. It supplies many interesting applications in the field of information and the quantum teleportation is one of them. Quantum teleportation, a method of indirectly transmitting quantum information via dual resources of classical communication and previously shared entanglement, is one of the most profound achievements of quantum information theory. Since Bennett et al. [4] proposed the first teleportation protocol, quantum teleportation has been intensively investigated [5][6][7][8][9][10][11][12][13][14][15][16][17] .GHZ and W class states are two kinds of important entangled states and they are always used as the quantum channel in quantum information. Recently, Briegel and Raussendorf [18] introduced a new class of N-qubit entangled state, cluster state [19,20] , which was different from both GHZ class and W class of N-qubit states. They presented that the cluster state was much more entangled than the GHZ state in some respects and they were more difficultly destroyed by local operations.