We present a practical roadmap to achieve optical cycling and laser cooling of asymmetric top molecules (ATMs). Our theoretical analysis describes how reduced molecular symmetry, as compared to diatomic and symmetric non-linear molecules, plays a role in photon scattering. We present methods to circumvent limitations on rapid photon cycling in these systems. We calculate vibrational branching ratios for a diverse set of asymmetric top molecules and find that many species within a broad class of molecules can be effectively cooled with a manageable number of lasers. We also describe methods to achieve rotationally closed optical cycles in ATMs. Despite significant structural complexity, laser cooling can be made effective using extensions of the current techniques used for linear molecules. Potential scientific impacts of laser-cooled ATMs span frontiers in controlled chemistry, quantum simulation, and searches for physics beyond the Standard Model.

中文翻译：

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分子不对称和光学循环：激光冷却不对称顶部分子

我们提出了一个实用的路线图，以实现不对称顶部分子（ATM）的光学循环和激光冷却。我们的理论分析描述了与双原子和对称非线性分子相比，降低的分子对称性如何在光子散射中起作用。我们提出了在这些系统中规避快速光子循环限制的方法。我们计算了一组不同的不对称顶部分子的振动支化比，发现使用可控数量的激光可以有效冷却多种分子中的许多物种。我们还描述了在ATM中实现旋转封闭光周期的方法。尽管结构上非常复杂，但可以通过扩展用于线性分子的当前技术来使激光冷却有效。