论文标题
通过四组分相关的电子结构计算，重新评估TLCL对激光冷却实验的潜力
Reassessing the potential of TlCl for laser cooling experiments via four-component correlated electronic structure calculations
论文作者
论文摘要
TLCL分子先前已在理论上进行了研究，并提议作为激光冷却搜索的有前途的候选者[X。 Yuan等。 al。 J. Chem。 Phys。，149，094306，2018]。从这些结果中，冷却过程将通过在\ sup {3}π\ sup {+} \ sub {0}和x \ sup {1}σ\ sup {+sup {+sub {0}状态之间进行过渡进行过渡。 A \ sup {3}π\ sup {+} \ sub {0}，这将禁止实验控制减速区域。在这里，我们通过采用四组分多次配置相互作用（MRCI）计算来重新审视该系统，并研究此类方法对A \ sup {3}π\ sup {+sup {+sup {+sub sub {0}和a \ sup {3}π\ sup的效果，因为理论与实验之间的基准。在可能的情况下，MRCI结果已通过运动耦合群集（EOM-CC）和极化传播器（PP）计算的四组分方程进行了交叉验证，并与之一致。我们发现TLF的结果对实验值非常封闭，而对于TLCL，A3π+0状态的寿命现在估计为175 ns，比以前所示的计算要短得多，因此产生了一种不同，更有利的冷却动力学。通过以数值方式求解速率，我们提供了证据表明TLCL可以具有与TLF相似的冷却特性。我们的研究还指出，在光学周期中增强刺激辐射以提高冷却效率的潜在益处。
The TlCl molecule has previously been investigated theoretically and proposed as promising candidates for laser cooling searches [X. Yuan et. al. J. Chem. Phys., 149, 094306, 2018]. From these results, the cooling process, which would proceed by transitions between a\sup{3}Π\sup{+}\sub{0} and X\sup{1}Σ\sup{+}\sub{0} states, had as potential bottleneck the long lifetime (6.04 μs) of the excited state a\sup{3}Π\sup{+}\sub{0} , that would prohibit experimentally control the slowing region. Here, we revisit this system by employing four-component Multireference Configuration Interaction (MRCI) calculations, and investigate the effect of such approaches on the calculated transition moments between a\sup{3}Π\sup{+}\sub{0} and a\sup{3}Π\sub{1} excited states of TlCl as well as TlF, the latter serving as a benchmark between theory and experiment. Wherever possible, MRCI results have been cross-validated by, and turned out to be consistent with, four-component equation of motion coupled-cluster (EOM-CC) and polarization propagator (PP) calculations. We find that the results of TlF are very closed to experiment values, while for TlCl the lifetime of the a3Π+0 state is now estimated to be 175 ns, which is much shorter than previous calculations indicated, thus yielding a different, more favorable cooling dynamics. By solving the rate-equation numerically, we provide evidence that TlCl could have cooling properties similar to those of TlF. Our investigations also point to the potential benefits of enhancing the stimulated radiation in optical cycle to improve cooling efficiency.
