The entropy squeezing of an atom with a k-photon in the Jaynes Cummings model is investigated. For comparison, we also study the corresponding variance squeezing and atomic inversion. Analytical results show that entr...The entropy squeezing of an atom with a k-photon in the Jaynes Cummings model is investigated. For comparison, we also study the corresponding variance squeezing and atomic inversion. Analytical results show that entropy squeezing is preferable to variance squeezing for zero atomic inversion. Moreover, for initial conditions of the system the relation between squeezing and photon transition number is also discussed. This provides a theoretical approach to finding out the optimal entropy squeezing.展开更多
The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial st...The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial state of thesystem and the relative coupling strength between the atom and the field on the atomic information entropy squeezingare discussed.Our results show that the squeezed direction and the frequency of the information entropy squeezing canbe controlled by choosing the phase of the atom dipole and the relative competing strength of atom-field,respectively.We find that,under the same condition,no atomic variance squeezing is predicted from the HUR while optimal entropysqueezing is obtained from the EUR,so the quantum information entropy is a remarkable precision measure for theatomic squeezing in the considered system.展开更多
In this paper,we analyzed squeezing in the information entropy,quantum state fidelity,and qubit-qubit entanglement in a time-dependent system.The proposed model consists of two qubits that interact with a two-mode ele...In this paper,we analyzed squeezing in the information entropy,quantum state fidelity,and qubit-qubit entanglement in a time-dependent system.The proposed model consists of two qubits that interact with a two-mode electromagnetic field under the dissipation effect.An analytical solution is calculated by considering the constants for the equations of motion.The effect of the general form of the time-dependent for qubit-field coupling and the dissipation term on the temporal behavior of the qubit-qubit entanglement,quantum state fidelity,entropy,and variance squeezing are examined.It is shown that the intervals of entanglement caused more squeezing for the case of considering the time-dependent parameters.Additionally,the entanglement between the qubits became more substantial for the case of time dependence.Fidelity and negativity rapidly reached the minimum values by increasing the effect of the dissipation parameter.Moreover,the amount of variance squeezing and the amplitude of the oscillations decreased considerably when the time dependence increased,but the fluctuations increased substantially.We show the relation between entropy and variance squeezing in the presence and absence of the dissipation parameter during the interaction period.This result enables new parameters to control the degree of entanglement and squeezing,especially in quantum communication.展开更多
The time evolution of entropy squeezing for the two-qubit XYZ Heisenberg model in an external uniform magnetic field is investigated in the language of quantum information. The effect of different parameters such as m...The time evolution of entropy squeezing for the two-qubit XYZ Heisenberg model in an external uniform magnetic field is investigated in the language of quantum information. The effect of different parameters such as magnetic field and anisotropy parameter on the properties of entropy squeezing and variance squeezing are discussed. It is shown that magnetic field and anisotropy parameter can enhance the entropy squeezing.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10674038 and 10604042)the National Basic Research Program of China (Grant No. 2006CB302901)
文摘The entropy squeezing of an atom with a k-photon in the Jaynes Cummings model is investigated. For comparison, we also study the corresponding variance squeezing and atomic inversion. Analytical results show that entropy squeezing is preferable to variance squeezing for zero atomic inversion. Moreover, for initial conditions of the system the relation between squeezing and photon transition number is also discussed. This provides a theoretical approach to finding out the optimal entropy squeezing.
基金National Natural Science Foundation of China under Grant No:10374025the Education Department of Hunan Province of China under Grant No.06A038
文摘The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial state of thesystem and the relative coupling strength between the atom and the field on the atomic information entropy squeezingare discussed.Our results show that the squeezed direction and the frequency of the information entropy squeezing canbe controlled by choosing the phase of the atom dipole and the relative competing strength of atom-field,respectively.We find that,under the same condition,no atomic variance squeezing is predicted from the HUR while optimal entropysqueezing is obtained from the EUR,so the quantum information entropy is a remarkable precision measure for theatomic squeezing in the considered system.
基金Taif University Researchers Supporting Project number(TURSP-2020/154),Taif University,Taif,Saudi Arabia.
文摘In this paper,we analyzed squeezing in the information entropy,quantum state fidelity,and qubit-qubit entanglement in a time-dependent system.The proposed model consists of two qubits that interact with a two-mode electromagnetic field under the dissipation effect.An analytical solution is calculated by considering the constants for the equations of motion.The effect of the general form of the time-dependent for qubit-field coupling and the dissipation term on the temporal behavior of the qubit-qubit entanglement,quantum state fidelity,entropy,and variance squeezing are examined.It is shown that the intervals of entanglement caused more squeezing for the case of considering the time-dependent parameters.Additionally,the entanglement between the qubits became more substantial for the case of time dependence.Fidelity and negativity rapidly reached the minimum values by increasing the effect of the dissipation parameter.Moreover,the amount of variance squeezing and the amplitude of the oscillations decreased considerably when the time dependence increased,but the fluctuations increased substantially.We show the relation between entropy and variance squeezing in the presence and absence of the dissipation parameter during the interaction period.This result enables new parameters to control the degree of entanglement and squeezing,especially in quantum communication.
基金Sponsored by the National Natural Science Foundation of China(10374007)
文摘The time evolution of entropy squeezing for the two-qubit XYZ Heisenberg model in an external uniform magnetic field is investigated in the language of quantum information. The effect of different parameters such as magnetic field and anisotropy parameter on the properties of entropy squeezing and variance squeezing are discussed. It is shown that magnetic field and anisotropy parameter can enhance the entropy squeezing.
