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71.
相互作用可控、相干时间较长的中性单原子体系具备在1 mm2的面积上提供成千上万个量子比特的规模化集成的优势,是进行量子模拟、实现量子计算的有力候选者.近几年中性单原子体系在实验上取得了快速的发展,完成了包括50个单原子的确定性装载、二维和三维阵列中单个原子的寻址和操控、量子比特相干时间的延长、基于里德伯态的两比特量子门的实现和原子态的高效读出等,这些工作极大地推动了该体系在量子模拟和量子计算方面的应用.本文综述了该体系在量子计算方面的研究进展,并介绍了我们在其中所做的两个贡献:一是实现了"魔幻强度光阱",克服了光阱中原子退相干的首要因素,将原子相干时间提高了百倍,使得相干时间与比特操作时间的比值高达105;二是利用异核原子共振频率的差异建立了低串扰的异核单原子体系,并利用里德伯阻塞效应首次实现了异核两原子的量子受控非门和量子纠缠,将量子计算的实验研究拓展至异核领域.最后,分析了中性单原子体系在量子模拟和量子计算方面进一步发展面临的挑战与瓶颈. 相似文献
72.
采用孤立实激发与自电离探测技术相结合的方法对Sm原子偶宇称高激发态进行了系统研究.按照不同的自电离通道将所测数据进行了分类和比较,并进行了详细讨论.不仅报道了许多收敛于不同电离限的Rydberg态的能级位置和跃迁的相对强度等信息,而且还把处于同一能域内的Rydberg态和价态进行了辨识.另外,不但提供了一种有效识别不同类型的高激发态的鉴别技术,而且还对处于41800 cm-1到43800 cm-1能域内的Rydberg态和价态的光谱特性进行了详细分析和讨论.
关键词:
自电离探测
Rydberg态
Sm原子 相似文献
73.
A.?Giuliani P.?Lim?o-Vieira D.?Duflot A. R.?Milosavljevic B. P.?Marinkovic S. V.?Hoffmann N.?Mason J.?Delwiche M.-J.?Hubin-Franskin 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,51(1):97-108
The electronic spectroscopy of isolated tetrahydrofuran (THF) in the gas phase has been investigated using high-resolution
photoabsorption spectroscopy in the 5.8–10.6 eV with absolute cross-section measurements derived. In addition, an electron
energy loss spectrum was recorded at 100 eV and 10° over the 5–11.4 eV range. The He(I) photoelectron spectrum was also collected
to quantify ionisation energies in the 9–16.1 eV spectral region. These experiments are supported by the first high-level
ab initio calculations performed on the excited states of the neutral molecule and on the ground state of the positive ion.
The excellent agreement between the theoretical results and the measurements allows us to solve several discrepancies concerning
the electronic state spectroscopy of THF. The present work reconsiders the question of the lowest energy conformers of the
molecule and its population distribution at room temperature.
Electronic supplementary material Supplementary Online Material 相似文献
74.
T. Amthor J. Denskat C. Giese N. N. Bezuglov A. Ekers L. S. Cederbaum M. Weidemüller 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(3):329-335
We investigate a possible mechanism for the autoionization of ultracold Rydberg gases, based on the resonant coupling of Rydberg
pair states to the ionization continuum.
Unlike an atomic collision where the wave functions begin to overlap,
the mechanism considered here involves only the long-range dipole
interaction and is in principle possible in a static system.
It is related to the process of intermolecular Coulombic decay (ICD).
In addition, we include the interaction-induced motion of the atoms and the effect of multi-particle systems in this work.
We find that the probability for this ionization mechanism can be increased in many-particle systems featuring attractive
or repulsive van der Waals interactions. However, the rates for ionization through resonant dipole coupling are very low.
It is thus unlikely that this process contributes to the autoionization of Rydberg gases in the form presented here, but it
may still act as a trigger for secondary ionization
processes.
As our picture involves only binary interactions, it remains to be investigated if collective effects of an
ensemble of atoms can significantly influence the ionization probability.
Nevertheless our calculations may serve as a starting point for the investigation of more complex systems, such as the coupling
of many pair states proposed in [P.J. Tanner et al., Phys. Rev. Lett. 100, 043002 (2008)]. 相似文献
75.
Vacuum ultraviolet photoabsorption spectra of CH3I 6s and 6s′ Rydberg states doped into supercritical argon, krypton, and xenon perturbers were measured from low density to the density of the triple point liquid at noncritical temperatures and on an isotherm near the perturber critical temperature. A full line shape analysis of these spectra was performed using a single set of intermolecular potential parameters for each dopant/perturber system. The resulting perturber induced shift of the simulated adiabatic transition of the 6s and 6s′ Rydberg states is presented as a function of perturber number density, and this shift illustrates a perturber critical point effect on the excitation energies of the molecular low-n Rydberg states. 相似文献
76.
The new experimental results on the effective quantum numbers and term energies of the highly excited odd-parity 4s4d 3D1,2,3 →4snf 3F2,3,4 Rydberg transitions of zinc have been presented. The experiment was performed using the three dye lasers simultaneously pumped by the second harmonic (532?nm) of the Q-switched Nd:YAG laser. The new observation includes the 4snf 3F3 (12?≤n?≤?50) series excited from the 4s4d 3D2 intermediate level. In addition, the 4snf 3F2 (12?≤n?≤?28) and 4snf3F4 (12?≤n?≤?33) series are observed from the thermally populated 4s4d 3D1,3 fine structure components. The ionization potential of zinc has been determined from the unperturbed 4snf 3F3 series as 75769.31?±?0.15?cm?1, which is in excellent agreement with the previously reported value. 相似文献
77.
78.
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
79.
80.