6 ms·
First-principles study on the electronic structure of Pb10−xCux(PO4)6O (x=0, 1)
- shusaku 3y agoLooks like the flood gates are open now. I’d expect a lot on the arxiv over the next few days. A priori, theory like this should be supportive (because calculations like these can’t prove the opposite) and experiment should be antagonistic (because the majority of things that you can accidentally make don’t superconduct at room temperature).
- marcosdumay 3y ago> because calculations like these can’t prove the opposite You meant the calculations can't show it's a superconductor, but can only show that some materials aren't?
- supriyo-biswas 3y agoOn that note, I’d like to see a paper about the failed replication attempts especially from the Indian lab that ended up with a paramagnetic insulator. Not that I’d understand anything, but a comparison of various attempts might lead us to the understanding of what works and what doesn’t.
- i-use-nixos-btw 3y agoI would love to see it too. Papers about failed experiments are worth a lot more than no papers about failed experiments. Alas, it is rare.
- daniel-cussen 3y ago[dead]
- yorwba 3y agoI think this paper is by the Indian lab you're talking about https://arxiv.org/abs/2307.16402 https://arxiv.org/abs/2307.16402
- adrian_b 3y agoThis and the other theoretical paper that has been linked in another HN thread agree that there are chances of superconductivity only when copper substitutes lead in certain crystal positions and not in the other positions. If this is correct, then it is expected that it will be very hard to produce good samples, because when impurity atoms are introduced in a crystal it is very difficult to control the final positions of the atoms, when there is little energy difference between alternatives. Minor differences in heat treatment can cause great differences in the electrical and magnetic properties of the samples. So it is likely that some time will pass until we will know for sure whether this material can be a superconductor, unless some laboratory gets very lucky. I suppose that the reason why the Korean team was not really ready to publish their results is because they are not able yet to produce material samples in a reproducible manner.
- cryptonector 3y agoIt may also be that this sort of crystal is impossible to construct with uniformity and in large quantities. But there's still new chemistry here.
- m3kw9 3y agoCan’t we work backwards and define a molecular structure for a SC and have software assisted program try to get this?
- hiddencost 3y agoParameter space is too large, and the simulations too expensive. People have been trying to get there for decades.
- mr_mitm 3y agoAs I understand it, a quantum computer might help here, but we're not there yet. It almost feels like we're on the brink of some revolutionary discoveries: quantum computers, room-temperature superconductors, fusion, general artificial intelligence. Unless it's all hype. I'm reluctant to be optimistic. Maybe the AI can help us develop a quantum computer with which we'll find useful materials to build a fusion reactor!
- fouric 3y agoHow might a quantum computer help? I was under the impression that there are only two quantum algorithms that are concretely known to provide exponential speedups for interesting problems relative to known classical state-of-the-art, and neither of them (Shor's and Grover's) appears to be useful for physics simulations. Was I mistaken?
- supernewton 3y agoThere's another problem, the original one that quantum computers were conceived to solve: Simulating a quantum system.
- calf 3y agoIt's been a while since college physics, are classic superconductors quantum mechanical effects as well?
- aaron695 3y ago[dead]
- stan_kirdey 3y agoas someone who don't know anything about anything I've been bugging GPT4 with the questions about this material, if you are curious to see the conversation https://chat.openai.com/share/50bceb29-7042-40aa-bc13-a974430948b9 https://chat.openai.com/share/50bceb29-7042-40aa-bc13-a97443... please, issue corrections in the comments if you have a second
- heyitsguay 3y agoI think this conversation demonstrates a misunderstanding of what GPT4 can and cannot do. You can get useful background information about DFT and molecular simulation, but definitely no first-principles reasoning about molecular properties.
- stan_kirdey 3y agogood to know, thank you for the note! maybe there can be a prompt that can investigate molecular properties?
- HPsquared 3y agoGPT can't run simulations or break any new ground.
- stan_kirdey 3y agomakes sense
- isatty 3y agoThis is not snark, just trying to understand but: why would you expect a text autocompleter to answer questions about cutting edge material science?
- stan_kirdey 3y agojust curious and trying to understand better what text autocompletion is capable of