whitequark changed the topic of #tinyqma to: design of an open hardware DDS-based QMA with a low-voltage dc/rf stage :: http://irclog.whitequark.org/tinyqma
<bofh__>
so how's the US grand tour so far?
<whitequark>
dense
<whitequark>
it's not all that different from the rest of the west, really
<bofh__>
I wouldn't have expected otherwise.
<bofh__>
I suspect a lot of it is due to a combo of a limited few mass media producers being popular and general commoditization / economy of scale for products
<whitequark>
hmmm
<whitequark>
I'm not sure it's about products. lifestyle, perhaps
<bofh__>
I guess some of that's due to media and information flow, some of it dates back to British empire/etc influence, and some of it to, well, how many different lifestyles are there that are common? (ignoring superficial differences)
<bofh__>
<shrug>
<bofh__>
I don't really have a good or even really an answer for why, despite the result not surprising me at all. Always mildly distressing when that's the case.
<whitequark>
right.
<bofh__>
wish I could stay in Geneva a bit longer
<bofh__>
(I'd wish for M2S2015 to be longer but I feel like it'll take me a month to process already and it's not even over)
<whitequark>
ohhhh neat
<bofh__>
strontium titanate continues to be bizarre and almost a bit magical
<bofh__>
FeSe superconducts around ~8K but if you grow a single layer of it on SrTiO3 you can make that go up to about 100K
<bofh__>
charge transport in that layer of course behaves basically nothing like that in bulk FeSe, of course
<bofh__>
also fascinating set of talks about vortex pinning methods that work in practise (vortices being probably the major reason why we don't use superconductors for power distribution everywhere already. everyone thinks it's only Tc but it's really not - LN2 is cheaper per litre than tap water here. it's that when you run a high enough current through a type-2 SC, it induces a magnetic field via faraday's law o
<bofh__>
f induction, this magnetic field induces vortices of charge disorder which then propagage, the propagation term in the Lagrangian basically adds a term to the conductivity that looks (and functions) exactly like a classical electrical resistance)
<bofh__>
(the other issue is that it's a pain in the ass to make wire out of ceramics)
<whitequark>
wow, nice
<whitequark>
"LN2 is cheaper per litre than tap water here.
<whitequark>
hahaha
<whitequark>
"term to the conductivity that looks (and functions) exactly like a classical electrical resistance" this is neat
<whitequark>
and yeah, wires are hard
<whitequark>
have i told you i have a BSCCO supplier quite near to me in moscow?
<bofh__>
no you haven't, that's quite nice. how much are they charging?
<whitequark>
haven't called them yet
<whitequark>
I expect it to be tractable though
<bofh__>
yeah, especially as the material itsself is downright cheap to make (my YBCO pucks cost me like $10, almost all of that for the Yttrium, and I can't imagine Bi being much pricier).
<whitequark>
yuppp
<bofh__>
also damnit, currently looking up cryocoolers on ebay and strongly debating buying one, lol
<bofh__>
(I guess I could always make a GM cryo design using some Helium and a refrigirator compressor... the tricky part there is making sure it doesn't overheat even slightly)
<whitequark>
that's actually what I am doing.
<whitequark>
I have this one: fehu.whitequark.org/files/Documentation/Cryogenics/Cryodyne model 22C⁄350C manual.pdf
<whitequark>
with a refrigerator compressor though you want to have a really good filter