오늘 킹스대학 연구팀과 같은 연구팀인 거 같다.
제1저자가 바뀌고 참여 인원은 거의 비슷하다.
8월 1일자 논문이 8월 21일자로 리버전됐다.
내용은 알아서 읽길..
https://arxiv.org/abs/2308.00698
Pb-apatite framework as a generator of novel flat-band CuO based physicsBased on DFT calculations, we present the basic electronic structure of CuPb9(PO4)6O (Cu-doped lead apatite, LK-99), in two scenarios: (1) where the structure is constrained to the P3 symmetry and (2) where no symmetry is imposed. At the DFT level, the former is predicted to be metallic while the latter is found to be a charge-transfer insulator. In both cases the filling of these states is nominally d9, consistent with the Cu2+ valence state, and Cu with a local magnetic moment ~0.7mB. In the metallic case we find these states to be unusually flat (0.2 eV dispersion), giving high DOS at EF that we argue can be a host for novel electronic physics, including potentially high temperature superconductivity. The flatness of the bands is the likely origin of symmetry-lowering gapping possibilities that would remove the spectral weight from EF. Since some experimental observations show metallic/semiconducting behavior, we propose that disorder is responsible for closing the gap. We consider a variety of possibilities that could possibly close the gap, but limit consideration to kinds of disorder that preserve electron count. For all possibilities we considered (spin disorder, O on vacancy sites, Cu on different Pb sites), the local Cu moment, and consequently the gap remains robust. We conclude that disorder responsible for metallic behavior entails some kind of doping where the electron count changes. We claim that the emergence of the flat bands should be due to weak wave function overlap between the Cu and O orbitals, owing to the directional character of the constituent orbitals. So, finding an appropriate host structure for minimizing hybridization between Cu and O while allowing them to still weakly interact should be a promising route for generating flat bands at EF which can lead to interesting electronic phenomena, regardless of whether LK-99 is a room-temperature superconductor.arxiv.org내가 내리고 싶은 결론은....
"네이처, 아직 안 끝났다."
Our finding, through calculation, of flat Cu-O bands at EF in Cu-doped Pb apatite show that this kind of system can be promising for superconductivity, though a critical aspect is whether or not the system will remain metallic, which is of course a requirement for supporting superconductivity.
몇몇 연구소뺴고 모조리 다 초전도체가 아닐꺼란 증거는없다는데 진짜 네이쳐수준 ㅋㅋㅋㅋㅋ
Therefore, finding an appropriate host structure for minimizing hybridization between Cu and O while allowing them to still weakly interact should be a promising route for generating flat bands at EF which can lead to interesting electronic phenomena, regardless of whether LK-99 is a room-temperature superconductor. 연구자들 더 연구하고 더 논문써라!!