[time-nuts] Current state of optical clocks and the definition of the second

[Attila Kinali]

On Tue, 13 Jan 2015 19:37:05 +0100
Attila Kinali <attila at kinali.ch> wrote:

> If you use a standard laser diode, these have a linewidth of
> around 20-100MHz. If you provide them the slightest feedback,
> they go down to 1MHz easily (ie just by adding some window glass
> infront of the laser, that reflects a tiny bit back).
> Using a more sophisticated scheme with a grating and you get into
> the range of 1-100kHz, which is pretty darn good, and enough for
> vapor cells with their broad lines. Wieman wrote a couple of papers
> on how to build such laser system [1-3]. Also worth a look are the two
> papers by Libbrecht [4,5]. For those who need some theory for
> calculation or as background [6] will be a good start. It also
> contains a lot of usefull references.

Oh.. i forgot to mention. The DIY holographcy community is full
of people who build their own narrow linewidth, stabilized lasers.
They have also quite a few, hands-on descriptions on how to build
grating based external cavity diode lasers. Especially W's website[1]
and blog[2].


			Attila Kinali

[1] http://redlum.xohp.pagesperso-orange.fr/argonlaser.html
[2] https://hololaser.wordpress.com/

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