Cesium-133 atoms emit a thin microwave spectral line when its 55th electron jumps back from an excited state orbital to its ground state (transition).

铯133原子发射一个细的微波谱线当它的第55个电子从受激态轨道跳回基态时(跃迁)。

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Once that is done, another laser pulse will jostle the virus from its ground state into an excited state, just as a single atom is excited by moving one of its electrons from a lower to a higher orbital.

ECONOMIST: An old thought experiment may soon be realised