Optimization of unconventional superconductivity through Fermi surface topology
Project/Area Number |
24340079
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Partial Multi-year Fund |
Section | 一般 |
Research Field |
Condensed matter physics II
|
Research Institution | Osaka University |
Principal Investigator |
Kuroki Kazuhiko 大阪大学, 理学(系)研究科(研究院), 教授 (10242091)
|
Co-Investigator(Kenkyū-buntansha) |
MACHIDA Masahiko 独立行政法人日本原子力研究開発機構, システム計算科学センター, 研究主幹 (60360434)
NAGAI Yuki 独立行政法人日本原子力研究開発機構, システム計算科学センター, 研究員 (20587026)
|
Project Period (FY) |
2012-04-01 – 2016-03-31
|
Project Status |
Completed (Fiscal Year 2015)
|
Budget Amount *help |
¥12,350,000 (Direct Cost: ¥9,500,000、Indirect Cost: ¥2,850,000)
Fiscal Year 2014: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000)
Fiscal Year 2013: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000)
Fiscal Year 2012: ¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000)
|
Keywords | フェルミ面トポロジー / スピン揺らぎ / 鉄系超伝導 / バンド構造 / 高温超伝導 / フェルミ面 / 電子相関効果 / 第一原理計算 / 超伝導 / 電子相関 / 不純物効果 / 第一原理バンド計算 / 多軌道性 / BiS2超伝導 / ペアリング対称性 |
Outline of Final Research Achievements |
In the iron-based superconductors, the second neighbor hopping can dominate over the nearest one. It is found that the s+- superconductivity, which is a second neighbor pairing state, can be enhanced even when the Fermi surface nesting is partially degraded. This explains why superconductivity is even enhanced when large amount of electrons are doped in the hydrogen doped 1111 iron-based superconductors. The comparison with the cuprates is interesting in this context. In the cuprates, the nearest neighbor hopping always dominates, and hence d-wave pairing, a nearest neighbor pairing state, is most favorable. In both of these high Tc families, there is a good matching between real space and momentum space. Namely, when these real space pairing states are Fourier transformed, the obtained gap functions in momentum space have large amplitude on places where the density of states is large. This gives a general guiding principle of enhancing superconductivity.
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Report
(5 results)
Research Products
(101 results)