作者leptoneta (台湾高山族自治区书记)
看板Physics
标题Re: [新闻] 韩国发现常温常压超导体
时间Tue Aug 1 12:09:27 2023
※ 引述《caseypie (吟游诗人)》之铭言:
: https://arxiv.org/abs/2307.12037
: 材料是Pb_{10-x}Cu_x(PO_4)_6O
: 在室温一大气压下测得零电阻和反磁性
: 麦斯纳效应影片:https://sciencecast.org/casts/suc384jly50n
: 文章内详细解释了合成方法
: 作者只用了修正的BCS来解释机制
: ----
: 要是真的,那韩国人真的要发明全宇宙了
就机制来说 National Lab是支持这个结果
https://twitter.com/Andercot/status/1686215574177841152
National Lab (LBNL) results support LK-99 as a room-temperature
ambient-pressure superconductor.
Simulations published 1 hour ago on arxiv support LK-99 as the holy grail of
modern material science and applied physics.
(
https://arxiv.org/abs/2307.16892)
以下为推特内文
Here's the plain-english explanation:
- The simulations modeled what the original Korean authors proposed was
happening to their material - where copper atoms were percolating into a
crystal structure and replacing lead atoms, causing the crystal to strain
slightly and contract by 0.5%. This unique structure was proposed to allow
this amazing property.
-
@sineatrix
from Lawrence Berkeley National Lab simulated this using heavy-duty compute
power from the Department of Energy, and looked to see what would happen to
the 'electronic structure' of this material, meaning, what are the available
conduction pathways in the material.
- It turns out that there are conduction pathways for electrons that are in
just the right conditions and places that would enable them to
'superconduct'. More specifically, they were close to the 'Fermi Surface'
which is like the sea-level of electrical energy, as in '0 ft above
sea-level.' It's believed currently that the more conduction pathways close
to the Fermi surface, the higher the temperature you can superconduct at (An
analogy might be how its easier for planes to fly close to the surface of the
ocean due to the 'ground effect' that gives them more lift.)
This plot in particular shows the 'bands', or electron pathways, crossing
above and below the Fermi surface.
- Lastly, these interesting conduction pathways only form when the copper
atom percolates into the less likely location in the crystal lattice, or the
'higher energy' binding site. This means the material would be difficult to
synthesize since only a small fraction of crystal gets its copper in just the
right location.
This is insanely bullish for humanity.
--
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※ 文章网址: https://webptt.com/cn.aspx?n=bbs/Physics/M.1690862970.A.501.html
1F:推 peter308: 预定诺奖了? 08/01 12:44
2F:推 linbryan: 里面提到这材料难做.因Cu难放在对位置.可预期杂质很多. 08/01 12:44
3F:→ linbryan: 我猜他只是测量bulk sample.如测量很小sample(lithograp 08/01 12:44
4F:→ linbryan: hy).有没帮助?还有单high Tc并没解决应用问题.重要在hig 08/01 12:44
5F:→ linbryan: h Ic, Hc. 08/01 12:44
6F:推 peter308: 似乎是用VASP 模拟的? 问题是第一原理模拟参杂系统 08/01 12:48
7F:→ peter308: 要建构的超晶包要很大 才能接近参杂的比率 08/01 12:49
8F:→ peter308: 有时候超晶包要到500-1000个原子 08/01 12:49
9F:→ peter308: 一般来说 就是看能待在费米能级附近有无平带 08/01 12:50
10F:→ peter308: 但更严谨的作法要用EPW(electron-phonon wannier) 套件 08/01 12:51
11F:→ peter308: 去做更进一步的验证 08/01 12:51
12F:→ meblessme: 如果好复现也不会丢出来了 08/01 12:52
13F:→ Bugquan: 问题是其它复现都没做出来,不过目前听说阿贡国家实验室 08/01 12:53
14F:→ Bugquan: ,有跟他们接洽,要直接分析他们手上的成品 08/01 12:53
15F:→ meblessme: 不过这不是ai最擅长的吗, 08/01 12:53
16F:→ meblessme: 接下来就看是人先找到还是ai先找到提高良率的办法了 08/01 12:53
17F:推 peter308: 有人手上有XRD数据吗? 我需要XRD的cif档就够 08/01 12:54
18F:→ peter308: 剩下的VASP我就能自己算 08/01 12:54
19F:→ Bugquan: 不过真的要是室温超导,其它组没复现,或是理论跟不上也 08/01 12:54
20F:→ Bugquan: 没差,起码东西拿出来让大家有个方向,也确定真有室温超 08/01 12:54
21F:→ Bugquan: 导 08/01 12:54
22F:推 KotoriCute: 没人能复现那就就跟金属氢差不多了 08/01 13:33
23F:推 Bugquan: 金属氢那位大哥Ranga Dias,今年"也"搞出室温超导 08/01 13:35
24F:→ yoyun10121: 这是模拟吧, 和复现是两回事 08/01 15:16
25F:→ hank780420: 真的要cif档直接连络原团队吧 他们连比对都用VESTA.. 08/01 15:44
26F:→ peter308: 下面那篇文章附录已经有结构档 08/01 15:51
27F:→ wohtp: 先不要说室温啦,这鬼东西在10K是不是超导? 08/01 17:27
28F:→ wohtp: 我好像都没看到有谁量这个。 08/01 17:27
29F:→ Eriri: 除去原作者 目前为止公开量过电阻的只有一组 没有观测到超 08/02 00:25
30F:→ Eriri: 导 08/02 00:25
31F:→ Eriri: 那篇文章量了150-300K的区间 08/02 00:27
32F:→ Eriri: 然後 DFT的那几篇文章 都没有证明有没有超导 其实根本没有 08/02 00:28
33F:→ Eriri: 处理超导 08/02 00:28
34F:→ Eriri: (事实上 哪怕宣称证明了…DFT的结果都不一定可信…) 08/02 00:29
35F:→ Eriri: 磁浮效应则可能真的存在 看起来不同的影片都观察到了 08/02 00:30
36F:推 shybaman: 以全世界没人鸟,韩国教授崔东植发明的ISB超导模型为基 08/02 01:02
37F:→ shybaman: 础,弄出来的室温超导体 08/02 01:02
38F:推 linbryan: 一般磁浮只要够轻dimagnetic +够大磁场就可做到.YBCO磁 08/02 01:33
39F:→ linbryan: 浮实验是强力小磁铁磁浮在YBCO上.但这个像是磁浮在大磁 08/02 01:33
40F:→ linbryan: 铁上 08/02 01:33
41F:→ Eriri: 今天又多了两篇类似的DFT文章… 08/02 12:06
42F:推 peter308: DFT很简单啊 难的是EPW的计算 08/02 12:45
43F:→ hank780420: 我也跟w大一样觉得很奇怪 量测都要放到PPMS了 08/02 13:50
44F:→ hank780420: 4k-400k的R-T跟M-T都量出来基本的吧..... 08/02 13:51