Rubidium standard

Rubidium standard

A rubidium standard is a frequency standard in which a specified hyperfine transition of electrons in rubidium-87 atoms is used to control the output frequency. A rubidium standard consists of a gas cell, which has an inherent long-term instability. This instability relegates the rubidium standard to its status as a secondary standard.

All commercial rubidium frequency standards operate by disciplining a crystal oscillator to the rubidium hyperfine transition of 6 834 682 610.904 324 Hz. The amount of light from a rubidium discharge lamp that reaches a photodetector through a resonance cell will drop by about 0.1% when the rubidium vapor in the resonance cell is exposed to microwave power near the transition frequency. The crystal oscillator is stabilized to the rubidium transition by detecting the light dip while sweeping an RF synthesizer (referenced to the crystal) through the transition frequency.

ee also

*Atomic clock
*Caesium standard
*hydrogen maser
* [http://tf.nist.gov/general/enc-re.htm#resonancefrequency NIST Time & Frequency A-Z Glossary - Resonance Frequency]
* [http://www.npl.co.uk/server.php?show=ConWebDoc.1727 Secondary Representation of the SI Second]
* [http://www.ptb.de/en/org/4/44/441/info2_e.htm PTB "Unit of Time"]

Source: from Federal Standard 1037C and [http://tf.nist.gov/general/enc-re.htm#resonancefrequency NIST]


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Rubidium — krypton ← rubidium → strontium K ↑ Rb ↓ …   Wikipedia

  • Rubidium oxide — IUPAC name Rubidium oxide …   Wikipedia

  • Rubidium nitrate — IUPAC name Rubidium nitrate …   Wikipedia

  • rubidium frequency standard — rubidžio dažnio etalonas statusas T sritis radioelektronika atitikmenys: angl. rubidium frequency standard vok. Rubidiumfrequenznormal, n rus. рубидиевый эталон частоты, m pranc. étalon de fréquence à rubidium, m …   Radioelektronikos terminų žodynas

  • Secondary frequency standard — In telecommunications, a secondary frequency standard is a frequency standard that does not have inherent accuracy, and therefore must be calibrated against a primary frequency standard. Secondary standards include crystal oscillators and… …   Wikipedia

  • Frequency standard — A frequency standard is a stable oscillator used for frequency calibration or reference. A frequency standard generates a fundamental frequency with a high degree of accuracy and precision. Harmonics of this fundamental frequency are used to… …   Wikipedia

  • Caesium standard — A caesium standard or caesium atomic clock is a primary frequency standard in which electronic transitions between the two hyperfine ground states of caesium 133 atoms are used to control the output frequency. They are one of the most accurate… …   Wikipedia

  • Isotopes of rubidium — Rubidium (Rb) has 24 isotopes, with naturally occurring rubidium being composed of just two isotopes; Rb 85 (72.2%) and the radioactive Rb 87 (27.8%). Normal mixes of rubidium are radioactive enough to fog photographic film in approximately 30 to …   Wikipedia

  • étalon de fréquence à rubidium — rubidžio dažnio etalonas statusas T sritis radioelektronika atitikmenys: angl. rubidium frequency standard vok. Rubidiumfrequenznormal, n rus. рубидиевый эталон частоты, m pranc. étalon de fréquence à rubidium, m …   Radioelektronikos terminų žodynas

  • Indian Standard Time — (IST) is the time observed throughout India and Sri Lanka, with a time offset of . India does not observe daylight saving time, (DST) or other seasonal adjustments, although DST was used briefly during the Sino–Indian War of 1962 and the… …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”