腔场耦合的二能级原子荧光谱北大核心

通过光与物质相互作用的主方程计算了强场激励的二能级原子与单模腔耦合的稳态荧光谱.在腔场的强耦合作用下,三峰Mollow谱的每个成分都分裂为多重的,这种现象由腔场使原子修饰态能级漂移而导致的,荧光谱的具体结构则依赖于驱动场的拉比频率和原子-腔的耦合系数.     

腔场耦合的二能级原子荧光谱

通过光与物质相互作用的主方程计算了强场激励的二能级原子与单模腔耦合的稳态荧光谱.在腔场的强耦合作用下,三峰Mollow谱的每个成分都分裂为多重的,这种现象由腔场使原子修饰态能级漂移而导致的,荧光谱的具体结构则依赖于驱动场的拉比频率和原子-腔的耦合系数.     

与热库耦合的光学腔内三原子间的纠缠动力学

研究了与热库耦合的光学腔中三个相互作用的二能级原子间的纠缠动力学.采用拉普拉斯变换和下限共生等方法,通过数值计算,分析了原子间三体纠缠的演化以及腔场与热库间的两体纠缠演化,讨论了各耦合参数对系统纠缠演化的影响.研究结果表明:原子间纠缠在短时间内随着原子间耦合强度的增加而增加,随原子与腔场耦合强度的增加而减小,在长时极限下趋于一稳定值;体系的非马尔科夫性由原子与腔场的耦合强度以及热库的谱宽度共同决定,当热库与腔场为强耦合时,原子与腔场组成的系统遵循非马尔科夫动力学,此时随着热库谱宽的增加,原子系统由非马尔科夫性变为马尔科夫性,随着谱宽的继续增加,原子与腔场组成的系统遵循马尔科夫动力学,原子系统又表现出非马尔科夫性;调整腔场与热库的失谐可以有效抑制热库耗散对纠缠衰减的影响.     

光学总论 量子光学

O431．2 2005042401 非等同两原子与双模光场相互作用的腔场谱=Cavity field spectra of two different atoms interacting with two-mode field[刊,中]／张桂明(聊城大学教育传播技术学院．山东, 聊城(252059)),李悦科…／／光电子·激光．-2005,16 (1)．-110-114 研究了非等同两原子与双模腔场模型的腔场谱,分析了谱结构随原子与腔场相对耦合常数的变化规律。结果发现,相对耦合常数对真空场、弱场、强场谱结构都有不同程度的影响;通过改变一模的光强,可以改变另一模腔场谱的频率,也可以改变相对耦合常数,同时改变两模腔场谱的频率。图7参15(严寒)     

依赖强度耦合的Λ型三能级Jaynes-Cummings模型的原子发射谱及腔场谱

在假设原子初始处于激发态并计入原子-场耦合强度依赖性的条件下,用本征函数法研究了Λ型三能级原子与单模腔场共振相互作用系统的原子发射谱和腔场谱。结果表明,基态能级裂距对谱结构有重要影响。发射谱和腔场谱的谱线随初场增强不发生合并现象,腔场谱对初场光子统计性质不敏感。     

非等同双原子与双模腔场拉曼相互作用模型的腔场谱

研究了非等同双原子与双模腔场拉曼相互作用模型的腔场谱,分析了谱结构随原子与腔场相对耦合常数R=g2/g1的变化规律,发现R对真空场、弱场、强场谱结构都有不同程度的影响.当R=1或R=0时,一般呈现简并的谱结构,而当R介于0与1之间时,腔场谱一般呈现复杂的非对称多峰结构.同时还发现,当R固定不变时,低频腔场初始场强对高频真空场谱结构也有较明显的影响. 关键词： 量子光学 腔场谱 拉曼相互作用 双模腔场     

依赖强度耦合的∧型三能级Jaynes-Cummings模型的原子发射谱及腔场谱

在假设原子初始处于激发态并计入原子-场耦合强度依赖性的条件下,用本征函数法研究了∧型三能级原子与单模腔场共振相互作用系统的原子发射谱和腔场谱.结果表明,基态能级裂距对谱结构有重要影响.发射谱和腔场谱的谱线随初场增强不发生合并现象,腔场谱对初场光子统计性质不敏感.     

两模腔场谱间的量子干涉

研究了高Q腔中单个二能级原子与两模二项式光场依赖强度耦合相互作用系统的腔场谱,给出了弱初始场条件下的数值结果,讨论了两模光场之间的量子干涉对腔场谱结构的影响. 发现当两模光场的频率差Δ>g（g为原子与腔场间的耦合常数）时,两模光场间的干涉效应对谱结构没有影响,系统的腔肠谱只是两模腔肠谱的简单叠加;当Δ≤g时两模腔场谱间的干涉比较明显. 在强初始场条件下,量子干涉效应可忽略. 关键词： 腔场谱 量子干涉 两模二项式光场     

非简并拉曼过程中交流斯塔克位移对腔场谱的影响

研究了原子与双模光场非简并拉曼耦合过程中交流斯塔克位移对腔场谱的影响.给出了原子处于基态且双模初始场为光子数态、相干态和压缩真空态时光谱结构的数值结果.发现数态光场在弱场条件下每模腔场谱都是三峰结构，在强场条件下则为双峰或单峰结构，相干态和压缩真空态光场的腔场谱在弱场或强场条件下都是双峰结构.随着斯塔克位移参数的变化,双峰的高度此长彼消. 关键词： 交流斯塔克位移 非简并拉曼过程 腔场谱     

等同双原子Jaynes-Cummings模型的量子特性及系统光谱

在全量子理论的背景下提出两个二能级原子分别与一单模腔场相互作用的系统模型,利用量子主方程和数值模拟计算等方法,研究该体系中腔场平均光子数、Mandel's Q因子及二阶量子相关度在非稳态时的变化规律。此外,对体系中原子及腔场中光谱结构进行了分析。结果表明:减小腔场耗散系数,增大原子间耦合系数,体系量子特性愈加明显。体系光谱呈现出Mollow三重峰结构,且原子辐射谱强度远大于腔场辐射谱强度。当原子跃迁频率与腔场跃迁频率为近共振时,Mollow峰值为三峰中最大值。此外,增大原子与腔场间耦合系数,可增大原子光谱的中峰强度;而增大腔场光谱的中峰强度,则需减小原子与腔场间耦合系数。     

Resonance fluorescence spectrum of a three-level atom driven by coherent and stochastic fields

The dressed-state populations and the resonance fluorescence spectrum of a V-type three-level atom driven by a strong coherent field and a weak stochastic one simultaneously are investigated. There can be significant population inversion due to the effect of the stochastic field. The atomic resonance fluorescence spectrum can be controlled by adjusting the frequency difference between the coherent field and the stochastic one and the coherent Rabi frequency. Peak suppression and line narrowing occur under appropriate conditions. Received 23 June 2000 and Received in final form 18 January 2001     

非线性光子晶体中原子辐射光场的非经典性质

讨论了非线性光子晶体微腔中二能级原子在相干场驱动下腔场的频谱特性及光子的统计性质.研究结果表明,当光子晶体的态密度很大时,如果腔场模与原子共振荧光Mollow峰的中心峰共振,则腔场的涨落压缩到量子散弹噪声之下,且与线性光子晶体微腔的情况相比其谱线峰值变大.当驱动场频率较大时光子服从亚Poisson分布,且非常接近Poisson分布. 关键词： 光子晶体 参量振荡 非弹性谱 二阶相关函数     

非线性光子晶体中原子辐射光场的非经典性质

讨论了非线性光子晶体微腔中二能级原子在相干场驱动下腔场的频谱特性及光子的统计性质.研究结果表明,当光子晶体的态密度很大时,如果腔场模与原子共振荧光Mollow峰的中心峰共振,则腔场的涨落压缩到量子散弹噪声之下,且与线性光子晶体微腔的情况相比其谱线峰值变大.当驱动场频率较大时光子服从亚Poisson分布,且非常接近Poisson分布.     

Cavity-Induced Enhancement of Squeezing in Resonance Fluorescence of a V-Type Three-Level Atom

The quadrature squeezing spectra in the resonance fluorescence of a V-type three-level atom driven by a coherent field and coupled to a single-mode cavity is investigated. For weak excitation, the fluorescence field exhibit squeezing in the out-of-phase quadrature. The coupling between the atom and the cavity mode can greatly enhance the squeezing centred at the laser frequency. More importantly, for strong excitation, under the effect of the cavity-atom coupling, the in-phase quadrature of fluorescence can exhibit two-mode squeezing at the two inner sideband frequencies. By working in the dressed-state representation and hiring secular approximation, we give an analytical explanation for the effect. The result shows, under appropriate conditions, the squeezing can be greatly enhanced by appropriately tuning the cavity resonant frequency.     

Auto-and cross-correlation functions of a one-atom laser in a regime of strong coupling

The spectral properties of an incoherently pumped one-atom laser operating in a regime of strong coupling are studied. The spectrum of the field outgoing from the cavity, the spectrum of resonance fluorescence of an atom, and the spectrum of the atom—field cross-correlation function are numerically calculated. Relations between the parameters of the system for which spectral lines corresponding to eigenstates of the Jaynes—Cummings Hamiltonian are resolved are found. A method for determining the widths of resonances from the spectrum of the atom—field cross-correlation function is proposed, and a procedure for measuring this function using spectroscopy of intensity fluctuations is described.     

压缩真空态中三能级原子的定态共振荧光

本文得到了与压缩白噪声真空库耦合的三能级原子在强相干驱动场作用下的定态共振荧光谱。结果表明谱分布强烈地依赖于库场压缩性及相干驱动场与库场压缩分量之间的位相差。 关键词：     

劣腔内二能级原子的双光子共振荧光光谱

研究了劣腔内二能级原子与单模腔场的双光子相互作用，腔内原子受外加固相干光场驱动，并向一般真空态自发辐射，通过腔镜内腔内注入压缩真空态光场，使腔模向压缩真空态光场衰减，本文利用劣腔近似条件得到原子约化密度算符主方程，在此基础上讨论了二能级原子的双光子共振荧光光谱。     

Cavity-damping-induced transitions in a driven atom- cavity system

We investigate the fluorescence spectrum of a two-level atom in a cavity when the atom is driven by a classical field. We show that forbidden dipole transitions in the Jaynes-Cummings ladder structure are induced in the presence of cavity damping, which deteriorates the degree of otherwise perfect destructive interference among the transition channels. With the larger cavity decay, these transitions are more enhanced.     

Statistics of discrete photodetection of resonance fluorescence in the Mollow sidebands

A method is proposed for generating conditional single-photon states with a high degree of purity in a single-mode cavity by successive discrete photodetection. The cavity is pumped by resonance fluorescence emission from a source atom driven by a classical field. The cavity is tuned to a Mollow sideband. A relation between detector parameters is found that makes it possible to interpret the detection of a probe atom in the excited state as unambiguous evidence that a pure single-photon state has been prepared in the cavity. An expression is derived for the prior probability of such an event, and dependence of the one-photon state population of the cavity field on detuning, relaxation rate, and time is examined.     

强光场驱动下内腔三能级原子的共振荧光谱

讨论了强相干激光场驱动下的内腔三能级原子的共振荧光谱，与自由空间情况相比，内腔谱从共振峰为中心向内压缩或向外扩张，但谱线的线型，线宽和强度没有变化，共振峰的线型取决于原子与驱动场之间的失谐程度，文中还谱线特征的形成原因作了分析。