Update of the highest Tc record on single-layered cuprate oxide superconductor Hg1201

• Project/Area Number: 15K17712
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: 一般財団法人総合科学研究機構(総合科学研究センター(総合科学研究室)及び中性子科学センター(研究開発
• Principal Investigator: Ishikado Motoyuki 一般財団法人総合科学研究機構(総合科学研究センター(総合科学研究室)及び中性子科学センター(研究開発, 中性子科学センター, 技師 (90513127)
• Research Collaborator: Takeshita Nao ; Funakoshi Kenichi ; Fujihisa Hiroshi
• Project Period (FY): 2015-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2015: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: 水銀系銅酸化物高温超伝導体 / 高圧下電気抵抗測定 / 高圧下X線回折実験 / 高圧下構造解析 / アニール条件 / 多結晶体 / 多結晶試料作製 / 単結晶育成 / ダイヤモンドアンビルセル / タリウム系銅酸化物試料 / 電気抵抗測定 / プロポーザル

Outline of Final Research Achievements

Among copper oxide high-temperature superconductors, a mercury-based copper oxide superconductor, HgBa2CuO4+d (Hg1201) has the highest superconducting transition temperature (Tc) with one CuO2 plane per unit cell. We performed transport (resistivity) and X-ray diffraction experiment under high pressure on Hg1201 as target material. Then, we examined the correlation between the rise of Tc and the crystal structural parameters. The experiments were performed on optimally-doped Hg1201 with Tc = 94-96 K and La2-xSrxCuO4 (Tc = 38 K) as a reference material. The lattice parameters became shorter with applying pressure. On the other hand, Tc tended to be saturated around 8GPa. Both behaviors seems to be not so correlated.

Academic Significance and Societal Importance of the Research Achievements

銅酸化物は現存する超伝導体の中では常圧下において最も高いTcを持つ物質系である。Hg系は銅酸化物の中でも最高のTcを持ちながら高圧下でTcと正の圧力効果を持つことが知られている。本研究では単位胞にCuO2面を一枚持つ中で最もTcの高いHg1201(Tc=96K)の高圧下におけるTcと相関する結晶構造因子を調べた。構造パラメータ(軸長など)は加圧と共に減少し、ゼロ電気抵抗から見たTcとは相関していないようである。高圧下の構造とTcに関する情報が得られた。

Research Products

• [Journal Article] Quasistatic internal magnetic field detected in the pseudogap phase of Bi2+xSr2-xCaCu2O8+δ by muon spin relaxation (2018)
  • Author(s): A. Pal, S.R. Dunsiger, K. Akintola, A.C.Y. Fang, A. Elhosary, M. Ishikado, H. Eisaki, J.E. Sonier
  • Journal Title: Physical Review B Volume: 97 Issue: 6
  • DOI: 10.1103/physrevb.97.060502
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Three-Dimensional Fermi Surface of Overdoped La-Based Cuprates (2018)
  • Author(s): Horio M.、Hauser K.、Sassa Y.、Mingazheva Z.、Sutter D.、Kramer K.、Cook A.、Nocerino E.、Forslund O.K.、Tjernberg O.、Kobayashi M.、Chikina A.、Schroeter N.B.M.、Krieger J.A.、Schmitt T.、Strocov V.N.、Pyon S.、Takayama T.、Takagi H.、et al.
  • Journal Title: Physical Review Letters Volume: 121 Issue: 7 Pages: 077004-077004
  • DOI: 10.1103/physrevlett.121.077004
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] High-energy spin fluctuation in low-Tc iron-based superconductor LaFePO0.9 (2018)
  • Author(s): Ishikado Motoyuki、Shamoto Shin-ichi、Kodama Katsuaki、Kajimoto Ryoichi、Nakamura Mitsutaka、Hong Tao、Mutka Hannu
  • Journal Title: Scientific Reports Volume: 8 Issue: 1 Pages: 16343-16343
  • DOI: 10.1038/s41598-018-33878-x
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] 水銀系銅酸化物高温超伝導体Hg1201の高圧下構造解析 (2016)
  • Author(s): 石角元志，竹下直, 舟越賢一,山岡人志,藤久裕司,後藤義人,平尾直久,大石泰生,河口沙織,永崎洋,伊豫彰
  • Organizer: 第57回高圧討論会
  • Place of Presentation: 筑波大学大学院会館
  • Year and Date: 2016-10-26