Chemistry in the ultracold regime enables fully quantum-controlled interactions between atoms and molecules, leading to the discovery of the hidden mechanisms in chemical reactions which are usually curtained by thermal averaging in the high temperature. Recently a couple of diatomic molecules have been cooled to ultracold regime based on laser cooling techniques, but the chemistry associated with these simple molecules is highly limited. In comparison, free radicals play a major role in many important chemical reactions, but yet to be cooled to submillikelvin temperature. Here we propose a novel method of decelerating CH₃, the simplest polyatomic free radical, with lithium atoms simultaneously by travelling wave magnetic decelerator. This scheme paves the way towards co-trapping CH₃ and lithium, so that sympathetical cooling can be used to preparing ultracold free radical sample.

超冷状态下的化学作用可实现原子与分子之间完全由量子控制的相互作用，从而导致发现化学反应中的隐藏机理，而这些化学反应通常是通过高温下的热平均来掩盖的。最近，已经基于激光冷却技术将几个双原子分子冷却到超冷状态，但是与这些简单分子相关的化学反应受到高度限制。相比之下，自由基在许多重要的化学反应中起主要作用，但尚未冷却至亚millikelvin温度。在这里，我们提出了一种通过行波电磁减速器同时用锂原子使最简单的多原子自由基CH ₃减速的新方法。该方案为共同捕获CH ₃铺平了道路 和锂，因此可以使用同感冷却来制备超冷自由基样品。