That precise characterization allowed them to target molecules with laser pulses lasting for one-quadrillionth of a second, or just long enough to set single electrons spinning.

在先前的研究中得到其原子水平上的结构，精确的结构特性允许他们用激光脉冲瞄准目标分子，并且只持续千万一份之一秒以使分子处以单电子自旋状态。

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The technology uses a femtosecond laser, which means it pulses at speeds of one-quadrillionth of a second.

ENGADGET: Researchers develop femtosecond laser that can diagnose, blast cancerous tumors

The sensor's imaging chip picks up the dark string immediately, even if only 1 femtogram (one-quadrillionth of a gram) of TNT is stuck to it.

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