Atomic clock

An atomic clock is a type of clock that uses an atomic resonance frequency standard as its counter. Early atomic clocks were masers with attached equipment. Today's best atomic frequency standards (or clocks) are based on more advanced physics involving cold atoms and atomic fountains.

See also

• Radio clock
• Optical Atomic Clock http://news.bbc.co.uk/2/hi/science/nature/4023777.stm