Pseudogap and superconducting gap in high temperature superconducting copper oxides

2014 Fiscal Year Final Research Report

• Project/Area Number: 24340083
• 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: TAJIMA Setsuko 大阪大学, 理学(系)研究科(研究院), 教授 (70188241)
• Co-Investigator(Kenkyū-buntansha): MIYASAKA Shigeki 大阪大学, 理学研究科, 准教授 (70345106) ; MASUI Takahiko 近畿大学, 理工学部, 准教授 (10403099) ; TANAKA Kiyohisa 分子科学研究所, 分子研, 准教授 (60511003)
• Co-Investigator(Renkei-kenkyūsha): TOHYAMA Takami 東京理科大学, 理学部, 教授 (70237056)
• Research Collaborator: UYKUR Ece 大阪大学, 理学研究科
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 高温超伝導 / 強相関 / 擬ギャップ / 超伝導ギャップ / 光学的性質

Outline of Final Research Achievements

We studied the pseudogap problem of the cuprates that is most important to elucidate the high temperature superconductivity mechanism. It has been clarified from the measurements of optical spectra that the pseudogap coexists with superconducting gap and not a precursor of superconductivity. A precursor of superconductivity was independently observed between the peusdogap temperature and superconducting temperature Tc. It was also revealed that the precursor temperature decreases with doping, being different from that of Tc, which suggests the importance of electron correlation for Cooper pairing. It is likely that the coexistence of pseudogap and superconducting gap causes the anomalous properties of superconducting gap.

Free Research Field

物性物理学