原子鐘

原子鐘係指以原子嘅激發狀態發出電磁波作為計時原理嘅鐘，係一種非常之精密嘅鐘。

Louis Essen（右）、Jack Parry（左）同佢哋整嘅世界第一台銫-133原子鐘

NIST物理學家Steve Jefferts（前）、Tom Heavner（後）同埋NIST-F2銫噴泉原子鐘，美國嘅民用時間標準。

出面網頁

• National Research Council Canada, FAQ: “What is a ‘cesium atomic clock’?”
• National Research Council Canada, archived content: Optical frequency standard based on a single trapped ion
• United States Naval Observatory Time Service Department
• PTB Braunschweig, Germany - with link in English language
• National Physical Laboratory (UK) time website
• NIST Internet Time Service (ITS): Set Your Computer Clock Via the Internet
• NIST press release about chip-scaled atomic clock
• NIST website
• Web pages on atomic clocks by The Science Museum (London)
• Optical Atomic Clock BBC, 2005
• Optical lattice clock; Journal of the Physical Society of Japan
• The atomic fountain
• National Research Council of Canada, archived content: Optical Frequency Comb – The Measurement of Optical Frequencies