A simple method is presented for generating multicomponent Schroedinger cat states through resonant atomfield interactions. In the scheme n two-level atoms, initially in ground states, are sent through a resonant cavi...A simple method is presented for generating multicomponent Schroedinger cat states through resonant atomfield interactions. In the scheme n two-level atoms, initially in ground states, are sent through a resonant cavity filled with a strong coherent field sequentially. Then state-selective measurements are performed on the atoms. The detections of the atoms in ground states collapse the cavity field onto a superposition of 2^n coherent states. This is the first way for producing superpositions of many coherent states through resonant atom-field interaction.展开更多
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...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.展开更多
We have studied the effect of phase shifted frequency modulation on two level atom with field interaction using Jaynes-Cummings model.Here the frequency of the interacting field is sinusoidally varying with time with ...We have studied the effect of phase shifted frequency modulation on two level atom with field interaction using Jaynes-Cummings model.Here the frequency of the interacting field is sinusoidally varying with time with a constant phase.Due to the presence of phase in the frequency modulation,the variation of population inversion with time is different from the standard case.There are no exact collapses and revivals in the variation of population inversion but it oscillates sinusoidally with time.In coherent field atom interaction the population inversion behaves as in the case of Fock state atom interaction,when frequency modulation with a non zero phase is applied.The study done with squeezed field has shown the same behavior of the population inversion.展开更多
基金The project supported by Fok Ying Tung Education Foundation under Grant No. 81008, National Natural Science Foundation of China under Grant Nos. 60008003 and 10225421, and Funds from Fuzhou University
文摘A simple method is presented for generating multicomponent Schroedinger cat states through resonant atomfield interactions. In the scheme n two-level atoms, initially in ground states, are sent through a resonant cavity filled with a strong coherent field sequentially. Then state-selective measurements are performed on the atoms. The detections of the atoms in ground states collapse the cavity field onto a superposition of 2^n coherent states. This is the first way for producing superpositions of many coherent states through resonant atom-field interaction.
基金Supported by the NSFC-Henan Talent Development Joint Fund under Grant No.U1204616the National Natural Science Foundation of China under Grant No.61378011the Fundamental Research of The Education Department of Henan Province of China under Grant Nos.13A140798,2010A140010
文摘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.
文摘We have studied the effect of phase shifted frequency modulation on two level atom with field interaction using Jaynes-Cummings model.Here the frequency of the interacting field is sinusoidally varying with time with a constant phase.Due to the presence of phase in the frequency modulation,the variation of population inversion with time is different from the standard case.There are no exact collapses and revivals in the variation of population inversion but it oscillates sinusoidally with time.In coherent field atom interaction the population inversion behaves as in the case of Fock state atom interaction,when frequency modulation with a non zero phase is applied.The study done with squeezed field has shown the same behavior of the population inversion.