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

Communications in Theoretical Physics

Effect of the Time-Dependent Atom-Field Couplings on Entanglement

Yao-Hua Hu, Yong-Gang Tan

Published Jul 1, 2014• 3 citations
Publisher

Abstract

A model containing two two-level atoms and a single-mode cavity is considered, and the effect of the time-dependent atom-field couplings on entanglement between the two atoms is studied. The results indicate that both for one-photon processes and for two-photon processes, the disappearance of the initial entanglement is delayed due to the linear modulation of the atom-field coupling coefficients as compared to the constant coupling model. The delayed time of the disappearance of the initial entanglement for the two-photon processes is much longer than that for the one-photon processes in the case of adiabatic variation.

DOI
10.1088/0253-6102/62/1/08

Related papers

Delaying disappearance of entanglement by the linear modulation of atom-field coupling

Yao-Hua Hu, Yong-Gang Tan

By considering a double Jaynes–Cummings (JC) model with linear modulation of the atom-field coupling coefficients, we investigate the entanglement evolution between two atoms, and focuss on the effect of the linear sweep on the entanglement. The results show that the entanglement is very sensitive to the linear modulation of the atom-field coupling coefficients. Both for one-photon processes and for two-photon processes, the disappearance of the initial entanglement is delayed due to the linear modulation as compared to the double standard JC model, and the delayed time is long or short depending on the value of the parameters in the modulation function. Moreover, the entanglement of the two atoms in the double standard JC model disappears periodically. However, this periodicity is completely lost in the linear modulation case. In addition, the larger the photon numbers in the cavities, the shorter the delayed time of the disappearance of the initial entanglement.

Physica Scripta•Jun 6, 2014•6 citations

On the interaction between a time-dependent field and a two-level atom

N. H. Abdel-Wahab, Ahmed Salah

In this paper, we study the interaction between the time-dependent field and a two-level atom with one mode electromagnetic field. We consider that the field of photons is assumed to be coupled with modulated coupling parameter which depends explicitly on time. It is shown that the considered model can be reduced to a well-known form of the time-dependent generalized Jaynes–Cummings model. Under special initial conditions, in which the atom and the field are prepared in the excited and the coherent states, respectively, the explicit time evolution of the wave function of the entire system is analytically obtained. Our proposal has many advantages over the previous optical schemes and can be realized in several multiple experiments, such as trapped ions and quantum electrodynamics cavity. The influence of the time-dependent field parameter on the collapses-revivals, the normal squeezing of the radiation, the anti-bunching of photons and the entanglement phenomena for the considered atomic system is examined. The linear entropy, the von Neumann entropy are used to quantify entanglement in the quantum systems. We noticed that these phenomena are affected by the existence of both the time-dependent coupling field and detuning parameters.

Modern Physics Letters A•Mar 14, 2019•11 citations

Adiabatic entanglement in two-atom cavity QED

Constantinos Lazarou, B. M. Garraway

We analyze the problem of a single mode field interacting with a pair of two level atoms. The atoms enter and exit the cavity at different times. Instead of using constant coupling, we use time-dependent couplings which represent the spatial dependence of the mode. Although the system evolution is adiabatic for most of the time, a previously unstudied energy crossing plays a key role in the system dynamics when the atoms have a time delay. We show that conditional atom-cavity entanglement can be generated, while for large photon numbers the entangled system has a behavior which can be mapped onto the single atom Jaynes-Cummings model. Exploring the main features of this system we propose simple and fairly robust methods for entangling atoms independently of the cavity, for quantum state mapping, and for implementing SWAP and controlled-NOT (CNOT) gates with atomic qubits.

arXiv:0810.0640•Physical Review A•Feb 19, 2008•19 citations

Entropy and entanglement in the Jaynes–Cummings model with effects of cavity damping

A.‐S. F. Obada, H. A. Hessian, A.‐B. A. Mohamed

The temporal evolution of entanglement for a single-mode field interacting with a two-level atom via intensity-dependent coupling in the off-resonant case has been studied, where the leakage of photon through the cavity is taken into account. The effects of cavity damping on the coherence properties of the atom and the field are studied. The amount of entanglement is compared with the total correlations. It is found that the atom–field system is inhibited from going into a pure state in the off-resonant case.

Journal of Physics B Atomic Molecular and Optical Physics•Jun 23, 2008•12 citations

Influence of entangled atoms on three-body entanglement measure in Tavis-Cummings model

Xie Fang-sen

The case that one of the two entangled identical two-level atoms interacts with a single-mode field among three-body entanglement was mainly considered. The results show that in initial the more the degree of entanglement of the two entangled atoms have, the more oscillation of the entanglement measure will have,and the more times of the maximally entanglement measure will obtain. Meanwhile, it was found that entanglement measure will be reduced when atomic coupling coefficient is larger than coupling coefficient between field and atom.

Chinese Journal of Quantum Electronics•Jan 1, 2004•0 citations

Effects of inhomogeneous couplings between atoms and a cavity field on entanglement dynamics

Jin‐Liang Guo, Yan Xia, He‐Shan Song

Based on the concept of concurrence, we have investigated the entanglement dynamics of two two-level atoms coupled to a single-mode cavity field with inhomogeneous couplings. We find that, for some initial states, the inhomogeneous couplings not only induce but also enhance the entanglement in the process of its evolution. In addition, considering the intrinsic decoherence proposed by Milburn, we also find that a proper value of inhomogeneous couplings can enhance the stationary entanglement, and as a result, the destructive effect of intrinsic decoherence on entanglement can be moderated by the inhomogeneous couplings.

Chinese Physics B•Jan 1, 2010•2 citations
A model containing two two-level atoms and a single-mode cavity is considered, and the effect of the time-dependent atom-field couplings on entanglement between the two atoms is studied. The results indicate that both for one-photon processes and for two-photon processes, the disappearance of the initial entanglement is delayed due to the linear modulation of the atom-field coupling coefficients as compared to the constant coupling model. The delayed time of the disappearance of the initial entanglement for the two-photon processes is much longer than that for the one-photon processes in the case of adiabatic variation.
By considering a double Jaynes–Cummings (JC) model with linear modulation of the atom-field coupling coefficients, we investigate the entanglement evolution between two atoms, and focuss on the effect of the linear sweep on the entanglement. The results show that the entanglement is very sensitive to the linear modulation of the atom-field coupling coefficients. Both for one-photon processes and for two-photon processes, the disappearance of the initial entanglement is delayed due to the linear modulation as compared to the double standard JC model, and the delayed time is long or short depending on the value of the parameters in the modulation function. Moreover, the entanglement of the two atoms in the double standard JC model disappears periodically. However, this periodicity is completely lost in the linear modulation case. In addition, the larger the photon numbers in the cavities, the shorter the delayed time of the disappearance of the initial entanglement.
In this paper, we study the interaction between the time-dependent field and a two-level atom with one mode electromagnetic field. We consider that the field of photons is assumed to be coupled with modulated coupling parameter which depends explicitly on time. It is shown that the considered model can be reduced to a well-known form of the time-dependent generalized Jaynes–Cummings model. Under special initial conditions, in which the atom and the field are prepared in the excited and the coherent states, respectively, the explicit time evolution of the wave function of the entire system is analytically obtained. Our proposal has many advantages over the previous optical schemes and can be realized in several multiple experiments, such as trapped ions and quantum electrodynamics cavity. The influence of the time-dependent field parameter on the collapses-revivals, the normal squeezing of the radiation, the anti-bunching of photons and the entanglement phenomena for the considered atomic system is examined. The linear entropy, the von Neumann entropy are used to quantify entanglement in the quantum systems. We noticed that these phenomena are affected by the existence of both the time-dependent coupling field and detuning parameters.
We analyze the problem of a single mode field interacting with a pair of two level atoms. The atoms enter and exit the cavity at different times. Instead of using constant coupling, we use time-dependent couplings which represent the spatial dependence of the mode. Although the system evolution is adiabatic for most of the time, a previously unstudied energy crossing plays a key role in the system dynamics when the atoms have a time delay. We show that conditional atom-cavity entanglement can be generated, while for large photon numbers the entangled system has a behavior which can be mapped onto the single atom Jaynes-Cummings model. Exploring the main features of this system we propose simple and fairly robust methods for entangling atoms independently of the cavity, for quantum state mapping, and for implementing SWAP and controlled-NOT (CNOT) gates with atomic qubits.
The temporal evolution of entanglement for a single-mode field interacting with a two-level atom via intensity-dependent coupling in the off-resonant case has been studied, where the leakage of photon through the cavity is taken into account. The effects of cavity damping on the coherence properties of the atom and the field are studied. The amount of entanglement is compared with the total correlations. It is found that the atom–field system is inhibited from going into a pure state in the off-resonant case.
The case that one of the two entangled identical two-level atoms interacts with a single-mode field among three-body entanglement was mainly considered. The results show that in initial the more the degree of entanglement of the two entangled atoms have, the more oscillation of the entanglement measure will have,and the more times of the maximally entanglement measure will obtain. Meanwhile, it was found that entanglement measure will be reduced when atomic coupling coefficient is larger than coupling coefficient between field and atom.
Based on the concept of concurrence, we have investigated the entanglement dynamics of two two-level atoms coupled to a single-mode cavity field with inhomogeneous couplings. We find that, for some initial states, the inhomogeneous couplings not only induce but also enhance the entanglement in the process of its evolution. In addition, considering the intrinsic decoherence proposed by Milburn, we also find that a proper value of inhomogeneous couplings can enhance the stationary entanglement, and as a result, the destructive effect of intrinsic decoherence on entanglement can be moderated by the inhomogeneous couplings.