Advances in Chip-Scale Atomic Frequency References at NIST
Svenja A. Knappe, V Shah, Alan Brannon, Vladislav Gerginov, Hugh Robinson, Z Popovic, Leo W. Hollberg, John E. Kitching
We present new advances in the development of chip-scale atomic frequency references. Coherent population trapping (CPT) resonances usually exhibit contrasts below 10 %, when interrogated with frequency modulated lasers. A relatively simple way to increase the resonance contrast to nearly 100 % will be discussed. It is based on the generation of an additional light field through a non-linear 4-wave mixing interaction in the atomic vapor 1. A similar method can also be used to create a beat signal at the CPT resonance frequency that can injection-lock a low-power microwave oscillator at 3.4 GHz directly to the atomic resonance2. This could lead to chip-scale atomic clocks (CSACs) with improved performance. A miniature microfabricated saturated absorption spectroscopy setup will be introduced3. It produces a signal for locking a laser frequency to optical transitions in alkali atoms. The Rb absorption spectra are comparable to signals obtained with standard table-top setups, although the rubidium vapor cell has an interior volume of only 1 mm3 and the volume of the entire spectrometer is around 0.1 cm3.
chip-scale atomic clock, CSAC, frequency reference, microfabrication, saturation spectroscopy
, Shah, V.
, Brannon, A.
, Gerginov, V.
, Robinson, H.
, Popovic, Z.
, Hollberg, L.
and Kitching, J.
Advances in Chip-Scale Atomic Frequency References at NIST, Proc. SPIE Conf., San Diego, CA, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=50588
(Accessed December 7, 2023)