Construction of a unified theory for magnetism and superconductivity in strongly correlated electron systems

2017 Fiscal Year Final Research Report

• Project/Area Number: 26800172
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Tohoku University
• Principal Investigator: Otsuki Junya 東北大学, 理学研究科, 助教 (60513877)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 強相関電子系 / 磁性 / 超伝導 / 動的平均場理論 / 重い電子 / 量子多体論 / データ科学 / スパースモデリング

Outline of Final Research Achievements

We established a theory that treats magnetism and superconductivity on equal footing. Starting from the dynamical mean-field theory, which has been widely applied to investigation of magnetism, spatial correlations are incorporated to address superconductivity. Applying the theory to the fundamental model for heavy-fermion systems, we revealed that there emerges a peculiar superconducting state that has not been expected in ordinary theories for superconductivity. This result affords a new insights into superconductivity that an exotic pairing could be induced by local-correlation effect.
In the latter of the period, we developed a new data-science approach to quantum many-body calculations. This approach is expected to play an crucial role in future applications of the "unified theory for magnetism and superconductivity" to realistic models for strongly correlated electron materials.

Free Research Field

強相関電子系理論