### Abstract

Using the single-mode approximation, we first calculate entanglement measures such as negativity and von Neumann entropy for a tetrapartite GHZ entangled system in nonuniform acceleration frame. We then analyse the whole entanglement measures, the algebraic residual measure π_{4} and geometric average measure Π_{4}. We find that the difference between π_{4} and Π_{4} is very slight or disappears with the increasing accelerated observers. The entanglement properties are compared among the different cases from two accelerated observers and others remaining stationary to all four accelerated observers, which are accelerated in nonuniform acceleration. The results presented here show that there still exists entanglement for the complete system even when acceleration r tends to infinity. The degree of entanglement is always equal to zero for the 1-1 tangle case. We also verify the existence of the Unruh effect even in nonuniform acceleration frame. It is also found that the von Neumann entropy increases with the increasing accelerated observers. It is interesting to see that S_{2} and S_{3} with two and three involved noninertial qubits first increase and then decrease with the acceleration parameter r, but S_{2} is equal to constant 1 for zero involved noninertial qubit. The special cases in the limit r_{a,b,c,d} → π/4 are also studied.

Original language | English |
---|---|

Article number | 163487 |

Journal | Optik |

Volume | 201 |

DOIs | |

State | Published - Jan 2020 |

### Fingerprint

### Keywords

- 03.65.Ud
- 03.67.-a
- 03.67.Mn
- 04.70.Dy
- Dirac field
- Entanglement
- GHZ state
- Nonuniform acceleration frame
- Tetrapartite

### Cite this

*Optik*,

*201*, [163487]. https://doi.org/10.1016/j.ijleo.2019.163487

}

*Optik*, vol. 201, 163487. https://doi.org/10.1016/j.ijleo.2019.163487

**Tetrapartite entanglement measures of GHZ state with nonuniform acceleration.** / Dong, Qian; Sun, Guo Hua; Toutounji, Mohamad; Dong, Shi Hai.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Tetrapartite entanglement measures of GHZ state with nonuniform acceleration

AU - Dong, Qian

AU - Sun, Guo Hua

AU - Toutounji, Mohamad

AU - Dong, Shi Hai

PY - 2020/1

Y1 - 2020/1

N2 - Using the single-mode approximation, we first calculate entanglement measures such as negativity and von Neumann entropy for a tetrapartite GHZ entangled system in nonuniform acceleration frame. We then analyse the whole entanglement measures, the algebraic residual measure π4 and geometric average measure Π4. We find that the difference between π4 and Π4 is very slight or disappears with the increasing accelerated observers. The entanglement properties are compared among the different cases from two accelerated observers and others remaining stationary to all four accelerated observers, which are accelerated in nonuniform acceleration. The results presented here show that there still exists entanglement for the complete system even when acceleration r tends to infinity. The degree of entanglement is always equal to zero for the 1-1 tangle case. We also verify the existence of the Unruh effect even in nonuniform acceleration frame. It is also found that the von Neumann entropy increases with the increasing accelerated observers. It is interesting to see that S2 and S3 with two and three involved noninertial qubits first increase and then decrease with the acceleration parameter r, but S2 is equal to constant 1 for zero involved noninertial qubit. The special cases in the limit ra,b,c,d → π/4 are also studied.

AB - Using the single-mode approximation, we first calculate entanglement measures such as negativity and von Neumann entropy for a tetrapartite GHZ entangled system in nonuniform acceleration frame. We then analyse the whole entanglement measures, the algebraic residual measure π4 and geometric average measure Π4. We find that the difference between π4 and Π4 is very slight or disappears with the increasing accelerated observers. The entanglement properties are compared among the different cases from two accelerated observers and others remaining stationary to all four accelerated observers, which are accelerated in nonuniform acceleration. The results presented here show that there still exists entanglement for the complete system even when acceleration r tends to infinity. The degree of entanglement is always equal to zero for the 1-1 tangle case. We also verify the existence of the Unruh effect even in nonuniform acceleration frame. It is also found that the von Neumann entropy increases with the increasing accelerated observers. It is interesting to see that S2 and S3 with two and three involved noninertial qubits first increase and then decrease with the acceleration parameter r, but S2 is equal to constant 1 for zero involved noninertial qubit. The special cases in the limit ra,b,c,d → π/4 are also studied.

KW - 03.65.Ud

KW - 03.67.-a

KW - 03.67.Mn

KW - 04.70.Dy

KW - Dirac field

KW - Entanglement

KW - GHZ state

KW - Nonuniform acceleration frame

KW - Tetrapartite

UR - http://www.scopus.com/inward/record.url?scp=85073162546&partnerID=8YFLogxK

U2 - 10.1016/j.ijleo.2019.163487

DO - 10.1016/j.ijleo.2019.163487

M3 - Artículo

AN - SCOPUS:85073162546

VL - 201

JO - Optik

JF - Optik

SN - 0030-4026

M1 - 163487

ER -