On Sun, 25 Mar 2018 14:13:56 -0500 Dana Whitlow <k8yumdoo...@gmail.com> wrote:
> Could it be that with the narrow-band laser emission the dip in > light transmission of the Rb cell is significantly improved? I know > that diode lasers are generally not paragons of virtue when it comes > to intensity noise, so I'm wondering what accounts for the claims of > better SNR with laser illumination. Those who use lasers, seem to mostly use a variant of saturated absorption spectroscopy, to get a sub-Doppler lock. Ie the laser is stabilized to a couple of 100Hz to a few kHz, at most. (An alternative, that nobody seems to use would be to use DVALL, which uses the the Zemann splitting to get a narrow line width) Using that, you get a laser that is very close to the the real absorption maximum of the vapor cell used, hence reducing light shift variation due to detuning/wander of the laser wavelength. As for intensity noise, yes, it's not glorious with lasers, but most papers I've read have a stabilization for that as well, so it gets attenuated a bit. Attila Kinali -- <JaberWorky> The bad part of Zurich is where the degenerates throw DARK chocolate at you. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.