We theoretically study the collective decay of two atoms trapped in a single mode cavity and we describe the evolution of the population of Dicke states. We show that the collective decay property is strongly dependen...We theoretically study the collective decay of two atoms trapped in a single mode cavity and we describe the evolution of the population of Dicke states. We show that the collective decay property is strongly dependent on the phase of atomic radiation and the speeding up of collective decay can only be observed in a bad cavity regime. For in-or out-phase case,this occurs due to the quantum interference enhancement, no matter which atom is excited initially. For π/2 phase, the speeding up of collective decay takes place if the first atom is excited at the beginning. However, it disappears due to the quantum interference cancellation if the second atom is excited. Compared with the in-phase and out-phase cases,we also show that the speeding up of collective decay can be significantly enhanced in strong coupling regime for π/2 phase, although one atom is decoupled to the cavity in this condition. The study presented here is helpful to understand the physical mechanism of collective decay in cavity quantum electrodynamics and it provides a useful method to control the collective decay phenomenon via quantum interference effect.展开更多
We utilize the general displacement operator proposed recently [C.Y. Chen, et al., Phys. Rev. A 74 （2006） 032328] to investigate a high-speed geometric quantum computation via vibrational mode decay of two trapped t...We utilize the general displacement operator proposed recently [C.Y. Chen, et al., Phys. Rev. A 74 （2006） 032328] to investigate a high-speed geometric quantum computation via vibrational mode decay of two trapped thermal ions. We find that, under some special conditions, the geometric phase gating is somewhat faster in the heating case than in the ideal case. We also investigate analytically the influence from the vibrational mode heating on the fidelity and the success probability of the implementation.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11504272,11774262,11474003,and 11504003)the National Key Basic Research Special Foundation(Grant No.2016YFA0302800)+2 种基金the Joint Fund of the National Natural Science Foundation of China(Grant No.U1330203)the Fund from the Shanghai Science and Technology Committee(STCSM)(Grant No.18JC1410900)the Natural Science Foundation of Anhui Province,China(Grant Nos.1408085MA19 and 1608085ME102)
文摘We theoretically study the collective decay of two atoms trapped in a single mode cavity and we describe the evolution of the population of Dicke states. We show that the collective decay property is strongly dependent on the phase of atomic radiation and the speeding up of collective decay can only be observed in a bad cavity regime. For in-or out-phase case,this occurs due to the quantum interference enhancement, no matter which atom is excited initially. For π/2 phase, the speeding up of collective decay takes place if the first atom is excited at the beginning. However, it disappears due to the quantum interference cancellation if the second atom is excited. Compared with the in-phase and out-phase cases,we also show that the speeding up of collective decay can be significantly enhanced in strong coupling regime for π/2 phase, although one atom is decoupled to the cavity in this condition. The study presented here is helpful to understand the physical mechanism of collective decay in cavity quantum electrodynamics and it provides a useful method to control the collective decay phenomenon via quantum interference effect.
基金Supported by the National Natural Science Foundation of China under Grant No. 10774042the Natural Science Fondation of Hunan Province under Grant No. 09JJ3121the National Fundamental Research Program of China under Grant Nos. 2005CB724500 and60490280
文摘We utilize the general displacement operator proposed recently [C.Y. Chen, et al., Phys. Rev. A 74 （2006） 032328] to investigate a high-speed geometric quantum computation via vibrational mode decay of two trapped thermal ions. We find that, under some special conditions, the geometric phase gating is somewhat faster in the heating case than in the ideal case. We also investigate analytically the influence from the vibrational mode heating on the fidelity and the success probability of the implementation.
