Tunnelling of molecules and quantum decay

在我们的日常经验中，被困在能量阱中的粒子只有在能量大于能垒的情况下才能逃脱；被困在碗里的弹珠一直呆在里面，除非它有足够的能量升到碗的顶部并出来。对于微观粒子，即使其能量小于势垒，粒子也有可能逃逸。这种现象被称为“隧道效应”。隧道效应的研究几乎只针对单个粒子。对分子隧穿的研究是最近才开始的。最简单的分子有两个原子，因此具有拉长的结构。分子隧穿的研究既有趣又具有挑战性，因为为了逃离能量势垒内的限制，两个原子都需要隧穿出来。

In our everyday experience, particles trapped inside energy wells can escape only if they have more energy than the energy barrier; a marble trapped in a bowl stays inside unless it has enough energy to rise to the top of the bowl and get out. For microscopic particles it is possible for the particle to escape even if its energy is less than the barrier. This phenomenon is called "tunnelling." Tunnelling has been investigated almost solely for single particles. Investigation into the tunnelling of molecules began relatively recently. The simplest molecule has two atoms and thus has an elongated structure. The study of tunnelling of molecules is interesting and challenging because, in order to escape confinement inside an energy barrier, both atoms need to tunnel out.