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In the course of this dissertation, a transportable optical frequency standard has been developed and characterized to disseminate the frequency of the calcium intercombination line at lambda approximately equal to 657 nm. The key components of the transportable frequency standard are a miniaturized thermal calcium beam apparatus and a frequency-stabilized diode laser system. A specially designed diode laser system in an extended cavity configuration was set up as a prerequisite to achieve the required narrow laser linewidth, and the laser frequency was stabilized to the intercombination line of atomic Calcium. The characterization of the transportable standard was done by comparing it with a stationary standard based on laser cooled atoms. The reproducibility of the frequency under different conditions was measured over a period of several months and showed a coincidence of all the values within an interval of 1.5 kHz. Compared to the presently widespread Iodine-stabilized He/Ne-lasers at 633 nm, the transportable Ca frequency standard offers a reduction of one order in magnitude in frequency uncertainty. Therefore, the developed transportable frequency standard will have a significant impact on the field of metrology and fundamental research in the future.

Additional information

Authors: KERSTEN P, Universität Kaiserslautern, Fachbereich Physik (DE)
Bibliographic Reference: Report: PTB-Opt-59 DE (1998) 152pp.
Availability: Available from Physikalisch Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (DE)
ISBN: ISBN 3-89701-133-6
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