共查询到19条相似文献,搜索用时 76 毫秒
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研究了动态各向同性光子晶体中二能级原子自发辐射的性质,主要讨论了光子晶体能带带边频率随时间作阶跃调制和三角函数周期调制两种情况下,原子上能级占据数随时间的演化特性.当光子晶体能带带边频率随时间作阶跃调制时,原子上能级占据数随时间的演化不仅和上能级与能带带边的相对位置δ有关,更依赖于阶跃调制发生的时刻.调制发生时刻不同,调制后原子上能级占据数随时间的演化也不同.当光子晶体能带带边频率随时间作三角函数周期调制时,二能级原子上能级占据数随时间作总体衰减的准周期振荡.通过选择调制频率和调制初相位可调控准周期振荡的频率、峰值与谷值的大小以及占据数的总体衰减速度等. 相似文献
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考虑真空涨落能量为负的特点,提出一个能够简洁描述原子与真空涨落相互作用的方程,得到原子处于激发态的概率随时间变化的关系,讨论了原子自发辐射的速率与真空涨落的强度的关系. 相似文献
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求解了经典电磁场中二能级原子系统的密度矩阵演化方程,得到了系统状态的相干特性x 相似文献
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研究了置于外部环境(热库)中的二能级原子在外加驱动场时原子的消相干问题.得到简并双光子过程中原子约化密度算符非对角元.在二能级原子的消相干被消除的情况下,讨论外加驱动场的特性.
关键词:
简并双光子过程
二能级原子
消相干性 相似文献
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研究了单个二能级原子自发辐射过程中原子和光场的Wigner-Yanse信息的变化情况. 分别计算了原子和辐射场的Wigner-Yanse信息. 结果表明:原子和光场的Wigner-Yanse信息都依赖于的平均值 , 并且当原子处于基态时, 光场的Wigner-Yanse信息达到最大值. 此外, 还发现原子与光场并不是同步地达到最大混合态. 相似文献
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研究了单个二能级原子自发辐射过程中原子和光场的Wigner-Yanse信息的变化情况. 分别计算了原子和辐射场的Wigner-Yanse信息. 结果表明:原子和光场的Wigner-Yanse信息都依赖于的平均值 , 并且当原子处于基态时, 光场的Wigner-Yanse信息达到最大值. 此外, 还发现原子与光场并不是同步地达到最大混合态. 相似文献
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光子晶体中二能级原子的自发辐射 总被引:3,自引:0,他引:3
研究光子晶体中二能级原子的自发辐射。由于光的局域化以及缀饰态之间的量子相互作用 ,由局域场、传输场、弥散场组成的原子的辐射场发生变化 :随着激发态能级由禁带移往通带 ,发现局域场中的能量通过弥散场向传输场转移。当局域场和传输场共存时 ,激发态能级上的原子布居数的演化具有准振荡行为 ;当局域场和传输场不共存时 ,原子布居数的演化不具有准振荡行为。另外 ,激发态能级上的稳态原子布居数也发生改变。这些性质不仅依赖于原子的激发态能级ω1与光子频率能带边缘ωc 的相对位置δ,同时也依赖于光子晶体中带边缘的光子态密度 ρ(ωk) (或带边光滑参数ε)。 相似文献
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Jing Nie Xiuyi Yang Qing-Xu Yu Chong Li 《International Journal of Theoretical Physics》2014,53(12):4291-4301
We have studied the non-Markovian decoherence dynamics of the two-level system in a composite environment, which consists of a spin-star environment and a boson reservoir. By use of the measures presented recently, we theoretically study the non-Markovianity of the dynamics of the model. 相似文献
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Using the photon closed orbit theory, the spontaneous emission rate of a polarized atom in a medium between two parallel mirrors is derived and calculated. It is found that the spontaneous emission rate of a polarized atom between the mirrors is related to the atomic position and the polarization direction. The results show that in the vicinity of the mirror, the variation of the spontaneous emission rate depends crucially on the atomic polarization direction. With the increase of the polarization angle, the oscillation in the spontaneous emission rate becomes decreased. For the polarization direction parallel to the mirror plane, the oscillation is the greatest; while for the perpendicular polarization direction, the oscillation is nearly vanished. The agreement between our result and the quantum electrodynamics result suggests the correctness of our calculation. This study further verifies that the atomic spontaneous emission process can be effectively controlled by changing the polarization orientation of the atom. 相似文献
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Counter-Rotating Transition Mediated Coherent Effects in Spontaneous Emission in a Three-Level Atom 下载免费PDF全文
The coherent effects including counter-rotating coupling on spontaneous emission are presented for a microwave driven V-type three-level atom. Novel coherent effects are realized: (i) There is an infinite series of spectral lines, which are separated by the microwave frequency, independent of the separation of the excited states, no matter whether the microwave transition is resonant or not. This is in sharp contrast to the case of the weak coupling, where the spectral interval is mainly determined by the separation of the excited states. (ii) Selective appearance and inhibition of the spectral lines are obtained simply by varying the microwave Rabi frequency. (iii) Spectral lines have a twofold structure. The physical mechanisms are analysed by employing the dressed states representation. 相似文献
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Phase Control of Spontaneous Emission of a Three-Level Atom in Two Bichromatic Fields 总被引:1,自引:0,他引:1 下载免费PDF全文
We use the relative phase difference of two bichromatic fields of equal frequency differences for the coherent control of spontaneous emission of a three-level atom in the A configuration, diffects such as selective and total cancellation of fluorescence decay are obtained simply by varying the phase difference. The phese dependence of fluorescence spectra is attributed to the fact that the four different field components induce the transitions in a closed loop configuratiou. 相似文献
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The reduced dynamics of a V-type three-level atom in a structure reservoir is presented,which has the exact solution in certain special condition.The Markovian and non-Markovian master equations for this composite system are solved and compared with the exact solution.The solving approach can be directly generalized to the solution of a V-type multilevel system dynamics interacting with a reservoir.The results further testify that these two kinds of master equations are exploited in different coupling regime,providing guidance for further application of these variants master equations to solve multilevel system dynamics without the exact solution. 相似文献