One news item, that nobody reported on last year is, that we now have three optical transitions measured to just 1e-16 (88Sr+), 1.8e-16 (87Sr) and 1.9e-16 (171Yb).
This means, that we now have three atom species that can be used for optical clocks, whose uncertainty is below what the realization of the second was, just a few years ago.
https://doi.org/10.1088/1681-7575/ade4d1
https://doi.org/10.1088/1681-7575/abc232
https://doi.org/10.1088/1681-7575/adb754
Today in things I have not done in a long time: Giving presentations on atomic clocks.
Coming back to OSHW atomic clocks. After thinking for a while. I think the cheapest option is to build a 87 Rb vapor cell coherent population trapping clock. I.e. one that shines a laser onto a vapor cell, which is modulated with half the hyperfine splitting.
The only special part needed would be the vapor cell, which can be had for 1k€ at Thorlabs (and others). Laser diodes are fairly easy to get, though need to be selected for modulation bandwidth.
1/3
Random musing of the day: What would it take to build an open source atomic clock?
Designing an atomic clock and making the design open is easy. Heck, there are plenty of schematics and drawings of commercial clocks online. But making it such that Joe and Jane Average could replicate it at home without any parts or devices that are hard to get or extremely expensive? That's a tough nut.
It's kind of weird. On one hand, we live in the golden age of atomic clocks. There are so many different research groups working on so many different types and species of atomic clocks. There is a whole zoo of them!
On the other hand, I don't think we ever had fewer companies selling atomic clocks than now. With the exception of Stanford Resarch, SpectraDynamics and µQuans, all atomic clock production is in the hand of 4 big companies, 3 of them being defense companies.
According to my representative sample, one in twelve people has thought about building their own atomic clock. This is way higher percentage than I expect it to be!
Don Moore’s Photo Album: Museum Findings – World War II
https://swling.com/blog/2025/01/don-moores-photo-album-museum-findings-world-war-ii/
#AtomicClocks #CWS52245 #GibsonGirl #HammurlandBC779ASuperPro #IndianaWarMemorialMuseum #LosAlamos #LosAlamosMuseum #NationalWASPWorldWarIIMuseum #USSIndianapolis #WesternElectricBC458A
Attila Kinali
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