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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α5/22,α5/20,α3/22和α3/20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. 相似文献
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本文主要从理论和实验上研究超冷铯(60D5/2)2 Rydberg分子的双色光缔合光谱.数值计算了铯60D5/2 Rydberg原子对态的长程电多极相互作用和(60D5/2)2 Rydberg分子的绝热势能曲线,获得了(60D5/2)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(60D5/2)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(60D5/2)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. 相似文献
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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α5/22,α5/20,α3/22和α3/20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 相似文献
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在铷原子的磁光阱中,通过光电离冷原子方法和稠密里德堡原子的自发演化方法产生了超冷等离子体.磁光阱中冷却并囚禁了10^7个原子,温度约为500μK,之后用一束脉冲激光将冷原子电离或者激发至高里德堡态,通过调节脉冲激光的能量控制离子数量或者里德堡原子的数量.利用延迟斜坡电场或脉冲电场引出超冷等离子体中的电子,对超冷等离子体的形成和演化进行了研究,并利用库仑势阱模型对实验结果进行了解释.实验结果表明,由于来自长寿命里德堡原子的贡献,里德堡原子自发演化形成的超冷等离子体的寿命比光电离形成的超冷等离子体的寿命长. 相似文献
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在铷原子的磁光阱中,通过光电离冷原子方法和稠密里德堡原子的自发演化方法产生了超冷等离子体。磁光阱中冷却并囚禁了10^7个原子,温度约为500μK,之后用一束脉冲激光将冷原子电离或者激发至高里德堡态,通过调节脉冲激光的能量控制离子数量或者里德堡原子的数量。利用延迟斜坡电场或脉冲电场引出超冷等离子体中的电子,对超冷等离子体的形成和演化进行了研究,并利用库仑势阱模型对实验结果进行了解释。实验结果表明,由于来自长寿命里德堡原子的贡献,里德堡原子自发演化形成的超冷等离子体的寿命比光电离形成的超冷等离子体的寿命长。 相似文献
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A new technique is described which allows Doppler-free, isotope-selective excitation of atoms by continuous wave laser radiation and continuous ionization of the atoms by an electric field. The atoms are excited to high Rydberg states in an electric-field-free region of a collimated atomic beam. Because the lifetimes of Rydberg atoms are long they can reach a spatially separated region of the atomic beam where they are ionized by a continuous electric field with a probability of unity. In the case of lithium we obtained a 103 times larger ion signal by field ionization of Rydberg atoms than by direct photoionization from low excited states. 相似文献
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We present energy spectra of electrons formed in the reaction of He(23 S, 21 S) with NO2 which have significantly improved counting statistics and resolution compared to earlier work. Further, we show spectra of the fluorescence light emitted in these reactions. The data are recorded in the same molecular beam apparatus as the electron spectra. For the metastable singlet state He(21 S) the spectra have not been measured before. We find that in addition to ionization excitation transfer takes place into Rydberg states of NO2**. Subsequently, the highly excited NO2** molecules dissociate into NO and atomic O* Rydberg atoms. 相似文献
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Experimental results of studying the spectrum of the microwave 37P-37S transition of Rydberg sodium atoms in a weak magnetic field (≤7 G) are reported. The populations of the Rydberg states were measured using the method of selective ionization with a pulsed electric field. When the magnetic field was parallel to the ionizing electric field, a good agreement between the calculated and experimental spectral shapes was observed, making it possible to determine the unknown polarization of the microwave radiation. In the case of the orthogonal configuration of the fields, the resonance structure was suppressed in the field ionization signals due to the strong influence of the magnetic field on the electron trajectories in the detection system. 相似文献
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E. A. Yakshina D. B. Tretyakov V. M. Entin I. I. Beterov I. I. Ryabtsev 《Journal of Experimental and Theoretical Physics》2020,130(2):170-182
The dipole blockade effect at laser excitation of mesoscopic ensembles of Rydberg atoms lies in the fact that the excitation of one atom to a Rydberg state blocks the excitation of other atoms due to the shift in the collective energy levels of interacting Rydberg atoms. It is used to obtain the entangled qubit states based on single neutral atoms in optical traps. In this paper, we present our experimental results on the observation of the dipole blockade for mesoscopic ensembles of 1–5 atoms when they are detected by the selective field ionization method. We have investigated the spectra of the three-photon laser excitation 5S1/2 → 5P3/2 → 6S1/2 → nP3/2 of cold Rydberg Rb atoms in a magneto-optical trap. We have found that for mesoscopic ensembles this method allows only a partial dipole blockage to be observed. This is most likely related to the presence of parasitic electric fields reducing the interaction energy of Rydberg atoms, the decrease in the probability of detecting high states, and the strong angular dependence of the interaction energy of Rydberg atoms in a single interaction volume. 相似文献
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Single colour three photon resonant ionization (2 + 1) is observed in atomic potassium vapour in a heat pipe oven using an
excimer laser pumped dye laser. Using wavelengths between 570 nm and 603 nm various2S and2D Rydberg states are populated by two photon excitation. Third photon of the same wavelength ionizes the atoms. Rydberg states
up ton ⋍ 50 are observed. Electric field as low as 1 V/cm causes extensive Stark mixing of the states. This results in progressively
higher three photon ionization signals via the perturbed2P and2F Rydberg states. The three photon ionization process is studied using both linearly and circularly polarized incident light.
The experiment shows qualitatively that the2P Rydberg states are perturbed primarily by the2D states in the prescence of an external electric field and to a much smaller extent by2S states. This is also explained theoretically by calculating the Stark mixing coefficients under the Bates and Daamgard (1949)
approximation. Implication for a similar effect in other alkali elements is discussed. 相似文献
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S. A. Aseyev Yu. A. Kudryavtsev V. V. Petrunin 《Applied physics. B, Lasers and optics》1993,56(6):391-398
The main properties of longitudinal and transverse electric field ionizers for fast Rydberg atoms n=21–40 have been investigated. The dispersion and the background due to collisional processes between fast atoms and residual gas molecules have been measured and calculated. The kinetic energy spread of ions formed by field ionization of Rydberg atoms and their trajectories have been calculated. The potassium beam energy was 3.9 keV. 相似文献
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We demonstrate two schemes for the coherent excitation of Rydberg atoms in an ultracold gas of rubidium atoms employing the three-level ladder system 5S1/2-5P3/2-n?j. In the first approach rapid adiabatic passage with pulsed laser fields yields Rydberg excitation probabilities of 90% in the center of the laser focus. In a second experiment two-photon Rydberg excitation with continuous-wave fields is applied which results in Rabi oscillations between the ground and Rydberg state. The experiments represent a prerequisite for the control of interactions in ultracold Rydberg gases and the application of ultracold Rydberg gases for quantum information processing. 相似文献
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<正>Using the time-dependent multilevel approach(TDML),this paper studies the dynamics of coherent control of Rydberg lithium atoms and demonstrates that Rydberg lithium atoms can be transferred to states of higher principal quantum number by exposing them to specially designed frequency-chirped laser pulses.The population transfer from n= 70 to n= 75 states of lithium atoms with efficiency of more than 90%is achieved by means of the sequential adiabatic rapid passages.The results agree well with the experimental ones and show that the coherent control of the population transfer from the lower n to the higher n states can be accomplished by the optimization of the chirping parameters and the intensity of laser field. 相似文献