ScienceJuly 6, 2026

attosecond

/ˈæt.oʊˌsɛk.ənd/

Definition

A unit of time equal to one quintillionth of a second (10^-18 seconds), used here to describe the ultra-short intervals required to measure electron motion.

Etymology

The word is a combination of the SI prefix 'atto-' (derived from the Danish 'atten', meaning eighteen) and the noun 'second'. It reflects the scientific convention of adding prefixes to units to denote powers of ten.

In the news

In this article, researchers use attosecond temporal resolution to track electron wave packets as they tunnel through energy barriers. This extreme precision is necessary to capture quantum events that occur at the fundamental speed limits of electron motion.

Ultrafast tunneling microscope reaches quantum space-time limit

Read the full article ↗

Wiley Analytical Science

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