Dynamical structure of superconducting gap function and pseudogap in cuprate high-temperature superconductors

2016 Fiscal Year Final Research Report

• Project/Area Number: 26800179
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Sakai Shiro 国立研究開発法人理化学研究所, 創発物性科学研究センター, 研究員 (80506733)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 高温超伝導 / 銅酸化物 / 動的平均場理論 / 動的構造 / 自己エネルギー / 隠れたフェルミオン

Outline of Final Research Achievements

I studied a theoretical model, which is considered to describe the low-energy electronic structure of cuprate high-temperature superconductors, based on numerical calculations. I particularly focused on the frequency-dependent structure of the self-energy, which describes the electronic correlation effect. As a result, I revealed that the high-temperature superconductivity, as well as an anomalous metallic (pseudogapped) behavior observed on its higher-temperature side, is induced by a hidden fermionic excitation emergent from the electron-correlation effect. This high-temperature superconducting mechanism is distinct from the conventional one mediated by bosonic excitations. This study also clarified the mathematical relationship between the pseudogap and the superconductivity.

Free Research Field

物性理論