Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Quantum-Atom Optics Downunder (QAO)

Multipartite entanglement of three trapped ions and the cavity field

S. Shelly Sharma, Eduardo de Almeida, Naresh Kumar Sharma

Published Jan 1, 2007• 0 citations
Publisher

Abstract

The entanglement dynamics of three trapped ion interacting with red sideband tuned single mode of a cavity field is examined. Analytical expressions for the state of three ions and the cavity field are used to obtain the global, four-way, three-way and two-way negativities. For the cavity field initially prepared in a number state, the probability of generating three ion W-state is calculated. Analytical expressions for K-way entanglement measures (K=2 to 4) are obtained and plotted as a function of time.

DOI
10.1364/qao.2007.qme34

Related papers

Multipartite entanglement of three trapped ions in a cavity and W-state generation

S Shelly Sharma, Eduardo de Almeida, Naresh K Sharma

A scheme to generate three qubit maximally entangled W-states, using three trapped ions interacting with the red sideband tuned single-mode field of a high finesse cavity, is proposed. For the cavity field initially prepared in a number state, the probability of generating the three-ion W-state is calculated. By using the ion-cavity coupling strengths achieved in experimental realizations, the interaction time needed for W-state generation is found to be of the order of 10 µs. It is found that for a fixed number of photons in the cavity the nature of entanglement of ionic internal states can be manipulated by an appropriate choice of the initial-state phonon number. The ionic qubits in the W-like state are found to be entangled to cavity photons. Analytical expressions for global negativity and partial K -way negativities ( K = 2 to 4) are obtained to study the evolution of entanglement distribution as a function of the interaction parameter. Reversible entanglement exchange between different entanglement modes is observed. For specific values of the interaction parameter, the three ions and photon–phonon system are found to have 4-partite entanglement, generated by 2-way and 3-way correlations.

arXiv:0804.1600•Journal of Physics B Atomic Molecular and Optical Physics•Aug 8, 2008•13 citations

Dynamics of Tripartite Entanglement

S. Shelly Sharma, Naresh Kumar Sharma

Maximally entangled states are of utmost importance to quantum communication, dense coding, and quantum teleportation. With a trapped ion placed inside a high finesse optical cavity, interacting with field of an external laser and quantized cavity field, a scheme to generate a maximally entangled three qubit GHZ state, is proposed. The dynamics of tripartite entanglement is investigated, using negativity as an entanglement measure and linear entropy as a measure of mixedness of a state. It is found that (a) the number of modes available to the subsystem determines the maximum entanglement of a subsystem, (b) at entanglement maxima and minima, linear entropy and negativity uniquely determine the nature of state, but the two measures do not induce the same ordering of states, and (c) for a special choice of system parameters maximally entangled tripartite two mode GHZ state is generated. The scheme presented for GHZ state generation is a single step process and is reduction-free.

arXiv:quant-ph/0502008•Physica Scripta•Jan 1, 2005•2 citations

Dynamics of Entanglement for Coherent Motional States of Two Trapped Ions in Cascaded Optical Cavities

Gao‐xiang Li, Zhang Fan, Shaoping Wu

We study the generation of an entangled motional coherent state of two distant ions trapped in two cascaded cavities, in which the motional mode of the each ion is coupled to the respective cavity field via a linear-mixing interaction. The master equation is solved analytically by using the characteristic function method. It is found that the generated entangled coherent state resulted from the initial preparation of an even coherent state is more robust than that from an odd coherent state under the dissipation of the cavity.

Chinese Physics Letters•Jan 30, 2006•3 citations

Simple schemes for preparation of multipartite entangled states of trapped ions

Feng Zhong

Three experimentally feasible schemes are proposed for generating multipartite entangled states of cold trapped ions.In the first scheme,a GHZ state can be simply synthesized in a single step. The second scheme is to prepare fully symmetric W states with two steps.The third scheme describes the sequential generation of linear cluster states.In addition,a method to create a larger cluster state was also presented by fuzing the end qubits of two smaller cluster states in order to decrease the distortion caused by decoherence,which can speed up the generation of large cluster states.The above schemes involve the collective interaction between multiple ions with the vibrational ground state and a large detuned laser. Compared with previous schemes,the above schemes have four advantages.Firstly,they do not require the vibrational mode of ions as memory.Secondly,they do not need to address the ions individually.Thirdly, they are free from the effects of phase fluctuation of laser field.Finally,they need less operations.

Chinese Journal of Quantum Electronics•Jan 1, 2011•0 citations

PAIRWISE ENTANGLEMENT DYNAMICS OF A MULTIPARTITE SYSTEM IN THE TAVIS–CUMMINGS MODEL

Feng Han, Yun‐Jie Xia

The pairwise entanglement dynamics in a multipartite system consisting of three two-level atoms A, B, C and a single-mode cavity field a is studied via negativity. Three atoms are arranged in such a way that atoms BC are embedded in and locally interact with the cavity while atom A is located in a spatially separate place outside of the cavity. Initially, atom-pair AB is prepared in a Bell-like state while atom C in a superposition of ground and excited state, |gC〉 and |eC〉. It shall be shown that all the pairwise negativities of the total system including atoms and cavity undergo qualitatively different evolutions. The so-called entanglement sudden death is observed for atom-pair AB under certain conditions and the entanglement transfer among all the possible degrees of freedom of the whole system is also discussed.

International Journal of Quantum Information•Oct 1, 2009•3 citations

Influence of second sideband excitation on the dynamics of trapped ions in a cavity

Xiang Liu, 方卯发

We study the dynamics of a trapped ion placed at an antinode of the standing wave inside a high finesse cavity with consideration of the second sideband excitation between the ionic internal levels and the light field. We investigate the entanglement of the three subsystems embodying the ionic internal levels, the vibrational mode of the ion and the cavity field.

中国物理B：英文版•Mar 16, 2005•0 citations
The entanglement dynamics of three trapped ion interacting with red sideband tuned single mode of a cavity field is examined. Analytical expressions for the state of three ions and the cavity field are used to obtain the global, four-way, three-way and two-way negativities. For the cavity field initially prepared in a number state, the probability of generating three ion W-state is calculated. Analytical expressions for K-way entanglement measures (K=2 to 4) are obtained and plotted as a function of time.
A scheme to generate three qubit maximally entangled W-states, using three trapped ions interacting with the red sideband tuned single-mode field of a high finesse cavity, is proposed. For the cavity field initially prepared in a number state, the probability of generating the three-ion W-state is calculated. By using the ion-cavity coupling strengths achieved in experimental realizations, the interaction time needed for W-state generation is found to be of the order of 10 µs. It is found that for a fixed number of photons in the cavity the nature of entanglement of ionic internal states can be manipulated by an appropriate choice of the initial-state phonon number. The ionic qubits in the W-like state are found to be entangled to cavity photons. Analytical expressions for global negativity and partial K -way negativities ( K = 2 to 4) are obtained to study the evolution of entanglement distribution as a function of the interaction parameter. Reversible entanglement exchange between different entanglement modes is observed. For specific values of the interaction parameter, the three ions and photon–phonon system are found to have 4-partite entanglement, generated by 2-way and 3-way correlations.
Maximally entangled states are of utmost importance to quantum communication, dense coding, and quantum teleportation. With a trapped ion placed inside a high finesse optical cavity, interacting with field of an external laser and quantized cavity field, a scheme to generate a maximally entangled three qubit GHZ state, is proposed. The dynamics of tripartite entanglement is investigated, using negativity as an entanglement measure and linear entropy as a measure of mixedness of a state. It is found that (a) the number of modes available to the subsystem determines the maximum entanglement of a subsystem, (b) at entanglement maxima and minima, linear entropy and negativity uniquely determine the nature of state, but the two measures do not induce the same ordering of states, and (c) for a special choice of system parameters maximally entangled tripartite two mode GHZ state is generated. The scheme presented for GHZ state generation is a single step process and is reduction-free.
We study the generation of an entangled motional coherent state of two distant ions trapped in two cascaded cavities, in which the motional mode of the each ion is coupled to the respective cavity field via a linear-mixing interaction. The master equation is solved analytically by using the characteristic function method. It is found that the generated entangled coherent state resulted from the initial preparation of an even coherent state is more robust than that from an odd coherent state under the dissipation of the cavity.
Three experimentally feasible schemes are proposed for generating multipartite entangled states of cold trapped ions.In the first scheme,a GHZ state can be simply synthesized in a single step. The second scheme is to prepare fully symmetric W states with two steps.The third scheme describes the sequential generation of linear cluster states.In addition,a method to create a larger cluster state was also presented by fuzing the end qubits of two smaller cluster states in order to decrease the distortion caused by decoherence,which can speed up the generation of large cluster states.The above schemes involve the collective interaction between multiple ions with the vibrational ground state and a large detuned laser. Compared with previous schemes,the above schemes have four advantages.Firstly,they do not require the vibrational mode of ions as memory.Secondly,they do not need to address the ions individually.Thirdly, they are free from the effects of phase fluctuation of laser field.Finally,they need less operations.
The pairwise entanglement dynamics in a multipartite system consisting of three two-level atoms A, B, C and a single-mode cavity field a is studied via negativity. Three atoms are arranged in such a way that atoms BC are embedded in and locally interact with the cavity while atom A is located in a spatially separate place outside of the cavity. Initially, atom-pair AB is prepared in a Bell-like state while atom C in a superposition of ground and excited state, |gC〉 and |eC〉. It shall be shown that all the pairwise negativities of the total system including atoms and cavity undergo qualitatively different evolutions. The so-called entanglement sudden death is observed for atom-pair AB under certain conditions and the entanglement transfer among all the possible degrees of freedom of the whole system is also discussed.