Atomic Clock

Clock that keeps time from atomic transition frequencies; the caesium transition defines the SI second itself.

Specifications & Metrics

type

Clocks & Standards

Core Principles & Analysis

• Based on the fact that atoms have quantised energy levels, with transitions driven by very specific frequencies of electromagnetic radiation.
• It provides the basis for the SI definition of the second, which fixes the numerical value of the caesium frequency.
• NIST-F2, a caesium fountain atomic clock, serves as a civilian time standard for the USA.

Sources

• Wikipedia: Atomic clock