Improved short-term stability of optical frequency standards: approaching 1 Hz in 1 s with the Ca standard at 657 nm.
نویسندگان
چکیده
For a neutral (40)Ca-based optical frequency standard we report a fractional frequency instability of 4 x 10(-15) in 1 s, which represents a fivefold improvement over existing atomic frequency standards. Using the technique of optical Bordé-Ramsey spectroscopy with a sample of 10(7) trapped atoms, we have resolved linewidths as narrow as 200 Hz (FWHM). With colder atoms this system could potentially achieve an instability as low as 2 x 10(-16) in 1 s. Such low instabilities are important for frequency standards and precision tests of fundamental physics.
منابع مشابه
Optical Frequency Standards and Measurements
We describe the performance characteristics and frequency measurements of two high-accuracy high-stability lasercooled atomic frequency standards. One is a 657-nm (456-THz) reference using magneto-optically trapped Ca atoms, and the other is a 282-nm (1064-THz) reference based on a single Hg ion confined in an RF-Paul trap. A femtosecond mode-locked laser combined with a nonlinear microstructur...
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ورودعنوان ژورنال:
- Optics letters
دوره 25 21 شماره
صفحات -
تاریخ انتشار 2000