His piece of LK-99 is much bigger than the tiny grains I've seen elsewhere.
On the other hand, his piece is much smaller than two pieces we saw from South Korea.
Andrew McCalip demonstrates synthesis of LK99
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Re: Andrew McCalip demonstrates synthesis of LK99
#42Earlier quoted context omitted.
I was wondering this, why do all the samples not completely float. If the sample is only partially superconducting, could you just smash it into smaller pieces and find a few floating ones? Or would the different domains be so small that you have to turn the sample into dust before you get a completely superconducting piece? Probably can not be answered in general as it heavily depends on the synthesis process?
Someone asked: > If you were to cut off the part that isn't lifting, do you reckon the entirety of the floaty half would float? AKA is this semi-float thing a purity issue? And Andrew responded [0]: > We wanted to do rock surgery, but I was scared we would shatter our biggest piece. It definitely has a piece that isn't contributing lift. I'm guessing once they've prepared more samples and had existing samples tested…
Re: Andrew McCalip demonstrates synthesis of LK99
#43His piece of LK-99 is much bigger than the tiny grains I've seen elsewhere.
It's made in USA baby!
I think you're joking, I'd 100% assume it, except that I ran into some truly bizarre US patriotism while trying to follow McCalip's updates a few days ago - last relevant one I could find was 'materials coming tomorrow' on 27th, but then I couldn't find anything about using them or any update. Just a decent into people tweeting (in thread) about how great America is, the best country, etc. Really surreal.
Think it was in replies here, but not logged in to tell: https://twitter.com/andrewmccalip/status/1684438158837153792
Re: Andrew McCalip demonstrates synthesis of LK99
#44Earlier quoted context omitted.
Twitter is basically broken if you don't login, compare this: https://twitter.com/andrewmccalip https://nitter.net/andrewmccalip In Twitter the latest tweet I see is from July, in Nitter is 22 minutes ago. Additionally in Twitter I get 3 notices/popups that I need to close.
Links behind logins wall/paywall should be totally forbidden, Twitter, Quora, news websites, etc. I don't even get why they are indexed by Google, as this is cloaking, and forbidden by the ToS (+ gets annoying)
Yeah that would be nice, but pretty hard to enforce.
I just read until I hit the first popup, then I back out.
I'd downvote if I could.
Re: Andrew McCalip demonstrates synthesis of LK99
#45Earlier quoted context omitted.
It's made in USA baby!
I think you're joking, I'd 100% assume it, except that I ran into some truly bizarre US patriotism while trying to follow McCalip's updates a few days ago - last relevant one I could find was 'materials coming tomorrow' on 27th, but then I couldn't find anything about using them or any update. Just a decent into people tweeting (in thread) about how great America is, the best country, etc. Really surreal. Think it wa…
It's jarring for us Euros (I dunno, ghosts of the war are still alive maybe?), but it's pretty normal stateside.
Re: Andrew McCalip demonstrates synthesis of LK99
#46Earlier quoted context omitted.
As it’s been theorized elsewhere, it may be that the production processes produce a material with only bits of the theorized superconductor in it, leading to the wiggling effect we see here as well as the Chinese replication video.
It is not a purity issue. On the other hand, 1D superconductors are expected to behave this way. See my other comments.
How do we know it isn't a purity issue?
Re: Andrew McCalip demonstrates synthesis of LK99
#47Interesting, this is being done in room temperature too. I suppose a few things I can conclude from this saga: 1. The synthesis process is much more complex than the original paper suggests. Every group except the original is unable to create a large piece of sufficient purity. 2. It seems like even with a pure sample, the entire structure might not be superconducting which leads it to tilt on one edge instead of com…
The original group also stated that they are preparing another paper specifically about this synthesis process IIRC. This would seem to indicate that the challenge is known and the initial omission either deliberate or another side effect of this absurdly gripping kdrama.
Re: Andrew McCalip demonstrates synthesis of LK99
#48This makes me extremely bullish about Varda Space, they have engineers of high quality and expertise that they could do a decent replication very quickly (if they got access to raw materials earlier, they might have been first to do so, comparable with the Chinese Groups) while working on their off time (from what I’ve seen of their twitter) and not a single big academic lab has managed to complete any sort of replic…
100% true and actually a very interesting statement. Can you imagine if he had tried to present this idea to the c-suite as a potential marketing or PR coup?!
Re: Andrew McCalip demonstrates synthesis of LK99
#49This makes me extremely bullish about Varda Space, they have engineers of high quality and expertise that they could do a decent replication very quickly (if they got access to raw materials earlier, they might have been first to do so, comparable with the Chinese Groups) while working on their off time (from what I’ve seen of their twitter) and not a single big academic lab has managed to complete any sort of replic…
> not a single big academic lab has managed to complete any sort of replication to date!
They are still busy getting approvals from three layers of management and one group of lawyers.
Re: Andrew McCalip demonstrates synthesis of LK99
#50Can anyone conduct a proper measurement of resistivity versus temperature and determine whether it's a superconductor or not?