Hi, On 03/04/2018 04:04 AM, Richard (Rick) Karlquist wrote: > When I was working on fiber optic communication test, > I remember hearing about lasers that were "tuned" with > variable Peltier coolers. Power consumption is critical in > a cesium standard that can run on batteries. Maybe > the power consumption of the coolers is a deal breaker.
The peltier elements is needed and nowdays integrated with laserdiodes. For telecom lasers, which is fully integrated, wavelength shift with temperature and Peltier elements is needed to temperature-stabilize them when you run DWDM, which is the telecom scenario which is close, as the ITU-T channels is 100 GHz apart on a 199 THz base for the 1550 nm window. So, peltier elements is needed for sure. However, I wonder if there really is much power involved. Cheers, Magnus > Rick > > On 3/3/2018 6:18 PM, Hal Murray wrote: >> Thanks. >> >> >> [email protected] said: >>> 2. Magnetic state selection, as used in the 5071A, would be replaced by >>> optical pumping. Len Cutler was heartbroken that HP/Agilent management >>> wouldn't fund this effort. >> >>> It turns out that, even now in 2018, optical pumping is not ready for >>> prime >>> time in a working standard because the lasers drift over time. >> >> Is there something fundamental in there, or is the lack of products >> because >> nobody has made the big investment required to figure out how to do it. >> >> What is the bandwidth of the laser? What happens if it drifts >> slightly? Can >> it be servoed? ... >> >> >> > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
