Calcium Optical Frequency Standardresearch at Ptb
نویسندگان
چکیده
At PTB we have developed an optical frequency standard based on laser cooled calcium atoms. A laser is frequencystabilized to the intercombination transition at a wavelength of 657 nm by means of time-domain atom interferences. The dependence of its frequency on various parameters was investigated by using different excitation schemes corresponding to phase sensitive and frequency sensitive atom interferometers. At present the total relative uncertainty of the measured frequency amounts to 2·10. As a result the Ca stabilized laser is among the optical frequency standards of lowest uncertainties. Further improvements using ultracold atoms are demonstrated.
منابع مشابه
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We describe the current status of the Ca optical frequency standards with laser-cooled neutral atoms realized in two different laboratories for the purpose of developing a possible future optical atomic clock. Frequency measurements performed at the Physikalisch-Technische Bundesanstalt (PTB) and the National Institute of Standards and Technology (NIST) make the frequency of the clock transitio...
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