atomic frequency การใช้

• Hyperfine qubits are extremely long-lived ( decay time of the order of thousands to millions of years ) and phase / frequency stable ( traditionally used for atomic frequency standards ).
• Curiously enough, it refers to the " M "-sample variance as " Allan variance " while referencing to Allan's paper " Statistics of Atomic Frequency Standards ".
• In 1956, the U . S . National Bureau of Standards and U . S . Naval Observatory started to develop atomic frequency time scales; by 1959, these time scales were used in generating the WWV time signals, named for the shortwave radio station that broadcasts them.
• Because Universal Time is synchronous with night and day, and more precise atomic-frequency standards drift away from this, however, UT is still used to produce a correction ( called a leap second ) to atomic time, in order to obtain a broadcast form of civil time that carries atomic frequency.
• The rare-earth element ytterbium ( Yb ) is valued not so much for its mechanical properties but for its complement of internal energy levels . " A particular transition in Yb atoms, at a wavelength of 578 nm, currently provides one of the world's most accurate optical atomic frequency standards, " said Marianna Safronova.
• However, the US Naval Observatory reports it is named after Gernot M . R . Winkler, who worked there between 1966 and 1995 and was awarded the 1988 I . I . Rabi Award for his " early development of worldwide clock synchronization through use of portable clocks; encouragement and support for the development of atomic frequency standards from their earliest days; and international leadership in the time and frequency community ."