[time-nuts] Better quartz crystals with single isotope ?

[djl]

Interesting indeed!  Seems as if there ought to be info about drawing 
crystals mono vs poly isotopic somewhere out there. Also some info about 
crystal grain boundaries that might be generated in a zone furnace 
drawing by isotope inclusions. Seems the boundaries are responsible for 
the sudden frequency shifts? My solid state physics is evanescent, but 
there ought to be a TN with some info...
Don


On 2018-04-22 10:19, Poul-Henning Kamp wrote:
> Silicon comes in a number of isotopes but 95% of it is Silicon-28.
> 
> When you make pure mono-crystaline silicon, you get 50-60% better
> thermal conductivity if you only use Silicon-28 atoms.
> 
> Yes, you read that right:  50-60% improvement for removing the
> remaining 5% other silicon isotopes, and for this and other reasons,
> sorting silicon atoms by isotope is now a thing, which amongst other
> side effects have made the Advogardo Project possible.
> 
> I can't help wonder if there may be similar interesting effects in
> quartz crystals, if they were monoisotopic ?
> 
> Several relevant mechanisms can be imagined, lower internal damping,
> higher stiffness etc. etc.
> 
> We know a LOT about quartz and have a very good theory for its
> behaviours, but i find no signs anybody has ever touched monoisotopic
> Quartz.
> 
> The obvious experiment is not rocket-science, nor does it demand
> inordinate resources for amateurs, see for instance from 03:35:
> 
> 	https://archive.org/details/59554KrystallosCF
> 
> But it is clearly beyond what I have time to persue.
> 
> Do we know anybody in the quartz business who needs a really cool
> research project ?
> 
> Poul-Henning

-- 
Dr. Don Latham
PO Box 404, Frenchtown, MT, 59834
VOX: 406-626-4304