User:Misibacsi/Készülő cikk/Rubídium oszcillátor
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Rubidium Oscillator The lowest priced members of the atomic oscillator family, rubidium oscillators operate at 6,834,682,608 Hz, the resonance frequency of the rubidium atom (87Rb), and use the rubidium frequency to control the frequency of a quartz oscillator. The optical beam from the rubidium lamp pumps the 87Rb buffer gas atoms into a particular energy state. Microwaves from the frequency synthesizer induce transitions to a different energy state. This increase the absorption of the optical beam by the 87Rb buffer gas. A photo cell detector measures how much of the beam is absorbed and its output is used to tune a quartz oscillator to a frequency that maximizes the amount of light absorption. The quartz oscillator is then locked to the resonance frequency of rubidium, and standard frequencies are derived from the quartz oscillator and provided as outputs as shown in the figure.
(ábra: működési vázlat, rubidium-oscillator-block-diagram.gif)
Rubidium oscillators continue to become smaller and less expensive, and offer perhaps the best price to performance ratio of any oscillator. Their long-term stability is much better than that of a quartz oscillator and they are also smaller, more reliable, and less expensive than cesium oscillators.
The Q of a rubidium oscillator is about 107. Undesirable shifts in the resonance frequency are due mainly to collisions of the rubidium atoms with other gas molecules and aging effects in the lamp system. These shifts limit the long-term stability. Stability is typically 1 x 10-11, and about 1 x 10-12 at one day. The frequency offset of a rubidium oscillator ranges from 5 x 10-10 to 5 x 10-12 after a warm-up period of a few minutes or hours, so they meet the accuracy requirements of most applications without adjustment.

