The87Sr optical frequency standard at PTB
نویسندگان
چکیده
منابع مشابه
Calcium Optical Frequency Standardresearch at Ptb
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 ato...
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Modern ac-dc transfer equipments can operate up to 1 GHz at least. These equipments and the related ac-voltage measurements may be attractive for calibrating high frequency power sensors in term of ac-dc transfer difference instead of effective efficiency. Furthermore, below 30 MHz, the ac-voltage standard can be also used as powerful alternative and complement to the microcalorimeter technique...
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متن کاملAbsolute frequency measurement of the neutral 40Ca optical frequency standard at 657 nm based on microkelvin atoms
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ژورنال
عنوان ژورنال: Metrologia
سال: 2011
ISSN: 0026-1394,1681-7575
DOI: 10.1088/0026-1394/48/5/022