Rydberg原子nS1/2→(n+1)S1/2双光子激发EIT-AT光谱

主要研究了热原子蒸气池中铯Rydberg原子nS_1/2→(n+1)S_1/2微波耦合的双光子光谱.铯原子基态(6S_1/2)、第一激发态(6P_3/2)、Rydberg态(69S_1/2)形成阶梯型三能级系统,弱探测光作用于基态到激发态6S_1/2→6P_3/2的跃迁,强耦合光则作用于6P_3/2→69S_1/2的Rydberg跃迁形成电磁感应透明(EIT)效应,实现对Rydberg原子的光学探测.频率fMW=11.735 GHz的微波场耦合69S_1/2→70S_1/2的Rydberg跃迁,形成微波双光子光谱.利用EIT-AT分裂光谱研究微波电场强度对双光子光谱的影响.研究表明:在强微波场作用时,EIT-AT分裂与微波场功率成正比,而弱微波场时的EIT-AT分裂与微波场功率成非线性依赖关系,理论计算与实验测量结果相一致.本文的研究对微波电场的精密测量具有一定的指导意义.     

Experimental investigation of slow light propagation in degenerate two-level system

Slowing a light pulse in a degenerate two-level system is observed with a double-frequency sweeping technique. The effects of coupling beam intensity, cell temperature and frequency detunings of the coupling and probe beams in resonance, on the slowing of light propagation in such a system are investigated. It is found that group velocities depend strongly on polarization combinations. A group velocity $v_{\rm g}$=6760m/s of light pulses in caesium vapour is obtained under the optimal parameters.     

超冷铯(60D5/2)2 Rydberg分子的双色光缔合光谱

本文主要从理论和实验上研究超冷铯（60D_5/2）₂ Rydberg分子的双色光缔合光谱.数值计算了铯60D_5/2 Rydberg原子对态的长程电多极相互作用和（60D_5/2）₂ Rydberg分子的绝热势能曲线,获得了（60D_5/2）₂ Rydberg分子的势阱深度和平衡间距.实验上利用双色光缔合超冷铯原子的方法制备了（60D_5/2）₂ Rydberg分子.其中,第一色激光（pulse-A）双光子共振激发种子Rydberg原子A;第二色激光（pulse-B,失谐于分子的束缚能）共振激发第二个Rydberg原子B,原子A与B由分子势阱束缚形成超冷（60D_5/2）₂ Rydberg分子.由脉冲场电离探测技术获得Rydberg分子的光缔合光谱,测量的Rydberg分子的势阱深度与理论计算结果相一致.     

Thermal-energy Pooling Collisions in Cesium Vapor6P3/2+6P3/2→7PJ+6S1/2

In this paper, the results of an experimental study on 6P3/2+6P3/2→7PJ+6S1/2 energy pooling collisions are presented. The experiment was carried out in cesium vapor using an external cavity diode laser for excitation under different temperatures. It is found that the response of fluorescence intensity to the frequency of excitation laser shows a two-peak phenomenon.     

Cs 39D态Rydberg原子Stark光谱的实验研究

本文从理论和实验上对Cs39D态Rydberg原子在弱电场作用下的Stark效应做了详细研究. 理论上利用数值方法计算了Cs原子39D态的Stark结构;实验上,采用两步激发超冷基态原子获得超冷Rydberg原子,通过场电离的方法获得了39D态的Stark光谱,测量获得α^5/2₂,α^5/2₀,α^3/2₂和α^3/2₀相应的极化率分别为：62(7),－146(13), 73(6) 和－106(20) MHz·V^-2cm²,实验结果与理论相符合. 关键词： Rydberg原子 Stark结构 场电离 极化率     

金属-氧化物-半导体硅发光器件在集成电路中的应用前景

集成硅光电子学的目的之一就是为大众市场创造应用广泛、成本低廉的光子互连工具.随着摩尔定律逼近理论极限,集成芯片的金属互连越来越跟不上芯片体积微型化、频率高速化和功耗分配精益化的需求.本文基于硅基发光器件的发展历程,详细论证了金属-氧化物-半导体结构硅发光器件在未来集成电路中的合理应用,提出了全硅光电集成电路在理论和工艺上的可行性.这种电路突破了传统芯片电互连码之间串扰的瓶颈,改善之后的互连速度理论可达光速,有望成为新一代集成芯片的主流.     

超冷铯Rydberg原子寿命的测量

本文从实验上采用两步激发超冷基态原子获得超冷Rydberg原子,通过选择场电离的方法获得超冷Rydberg原子的离子信号.改变延迟时间测得Rydberg原子布居数随时间的变化关系,用两种方法拟合实验数据得到36D和34S态原子的有效寿命,与现有理论结果一致. 关键词： Rydberg原子 寿命 黑体辐射 场电离     

Experimental Observation of Autler-Townes Splitting in Sub-Doppler Selective Reflection Spectroscopy

We present an experimental study of Autler-Townes splitting of non-linear selective reflection spectroscopy in a A-type driven three-level system. The sub-Doppler reflection spectroscopy is observed and the Autler-Townes splitting is measured as functions of the different coupling laser intensity and detuning. The coherent drive splits the excited state into two dressed states and an Autler-Townes splitting emerges in the probe reflection. The experimental results are in good agreement with theoretical fit.     

Electric dipole moments of lithium atoms in Rydberg states

Recently, the diverse properties of Rydberg atoms, which probably arise from its large electric dipole moment(EDM),have been explored. In this paper, we report electric dipole moments along with Stark energies and charge densities of lithium Rydberg states in the presence of electric fields, calculated by matrix diagonalization. Huge electric dipole moments are discovered. In order to check the validity of the EDMs, we also use these electric dipole moments to calculate the Stark energies by numerical integration. The results agree with those calculated by matrix diagonalization.     

超冷(36D5/2+6S1/2)里德伯分子的制备及其电偶极矩的测量

里德伯-基态分子由一个里德伯原子和一个基态原子组成,束缚机制是里德伯电子与基态原子的低能电子散射相互作用.理论上,通过低能电子散射Fermi赝势模型,数值计算了铯(36D_5/2+6S_1/2)里德伯-基态分子的绝热势能曲线,提取了里德伯分子的束缚能和平衡核间距等光谱参数.实验上,利用双光子光缔合技术成功制备了散射三重态(^T∑,Triplet)和散射单重态-三重态混合(^S,T∑,Mixed)形成的里德伯-基态分子,获得了里德伯分子的光缔合光谱,测量的势阱深度与理论计算结果相吻合.另外,以散射三重态为例,分析了里德伯分子的光缔合光谱在外加电场中的展宽现象,获得其平均永久电偶极矩|d|为(12.10±1.65) Debye ((4.76±0.65)ea₀),与理论计算结果保持一致.该研究为实验上制备D态里德伯-基态分子提供了可行的实验方案,对理解里德伯分子的光谱特性具有重要意义.