[time-nuts] HP5065B !!!

[Attila Kinali]

On Mon, 29 Apr 2013 06:28:55 +1200
Bruce Griffiths <bruce.griffiths at xtra.co.nz> wrote:

> Attila Kinali wrote:
    
> > Considered, yes, tried, no. From what i've read sofar, this system
> > has the problem of locking the laser wavelength onto the right
> > absorbtion line. IIRC the linewidth of Rb in a vapor cell is a couple
> > of 10kHz to a few 100kHz. Using an ECDL you get a laser linewidth of
> > less than 1MHz easily, usally in the range of a few 100kHz and less.
> > Ie. the laser would need to be kept on the absorption line with a stability
> > of a couple of 100kHz at most. Using just a laser diode (without the
> > external cavity) with its linewidth of>100MHz makes it actually a
> > little bit easier to handle.
> >    
> But the pump laser is then too noisy to allow a low noise rubidium 
> standard to be implemented.
> With a temperature stabilised ECDL locking the laser to the D1 or D2 
> rubidium absorption feature whilst simultaneously stabilising the laser 
> beam power can easily be achieved.

Yes, there would be a lot more noise and also multi-mode ringing.
But the question is, how do you reliable lock a narrow laser line
to the right absorption line? How would the control loop work to
keep the laser there?

I'm asking mostly out of interest, because i have no clue how this
is done. Although i've read many papers on laser spectroscopy and
how to acheive even better atomic clocks using lasers, none of those
papers mentiones how to get the laser there where it should be and
how to keep it there.

			Attila Kinali
-- 
The people on 4chan are like brilliant psychologists
who also happen to be insane and gross.
		-- unknown