2002 Fiscal Year Annual Research Report

超高分解能光電子分光装置の開発と高温超伝導体準粒子の研究

Research Project

Project/Area Number	14102006
Research Institution	Tohoku University
Principal Investigator	高橋隆東北大学, 大学院・理学研究科, 教授 (00142919)
Co-Investigator(Kenkyū-buntansha)	相馬清吾東北大学, 大学院・理学研究科, 日本学術振興会特別研究員DC1 佐藤宇史東北大学, 大学院・理学研究科, 助手
Keywords	高温超伝導体 / 角度分解光電子分光 / 準粒子 / 超伝導ギャップ / フェルミ面
Research Abstract	本年度は、研究推進の中核装置である「超高分解能角度分解光電子分光装置」の建設と整備を中心として研究を遂行した。装置の建設・整備に関しては以下の具体的作業を行った。 1.装置のエネルギー及び角度分解能向上を図るため、電子エネルギー分析器に、新型「2次元電子検出器」を装着し、その調整と最適化を行った。これにより、現時点で、角度分解能0.1°を達成する事に成功した。 2.紫外線励起光源に「トロイダル回折格子」を装着し、調整・最適化を行った。この回折格子の装着及び上記のエネルギー分析器の改良(新型2次元電子検出器の装着)により、ガス試料の測定で、エネルギー分解能1.9meVを達成する事に成功した。 3.「角度可変型試料マニピュレーター」、「ヘイウムクライオスタット」および「超高真空試料チェンバー」を設計した。上記の装置の建設・整備と並行して、3枚のCuO_2層を持ちBi系高温超伝導体では最高の超伝導転移温度を持つBi_2Sr_2Ca_2Cu_3O_<10>(以下Bi2223と略す)について、高分解能角度分解光電子分光測定を行い、以下の新しい知見を得た。 4.電子帯バンド構造およびフェルミ面の実験的決定に成功し、Bi2223は、1枚及び2枚CuO_2層を有する他のBi系高温超伝導体と同様に、ブリルアンゾーン中X点を中心とした大きなホール的フェルミ面を持つことを見出した。 5.フェルミ面上の精密測定から、超伝導ギャップの対称性がdx^2-y^2であることを見出した。 6.Bi2223の結果と、他のBi系高温超伝導体の結果を比較することにより、超伝導体の特徴的エネルギー(超伝導ギャップ、擬ギャップ開閉温度等)が、CuO_2層の枚数ではなく、それぞれの物質の最高超伝導転移温度にスケールする事を見出した。

Research Products

(19 results)

All Other

All Publications (19 results)

[Publications] T.Sato: "Low energy excitation and scalling in Bi_2Sr_2Ca_<n-1>Cu_nO_<2n+4>(n=1-3) : Angle-resolved photoemission spectroscopy"Phys. Rev. Lett.. 89. 067005-1-067005-4 (2002)
[Publications] S.Nishina: "Zn-substitution effects on the low-energy quasiparticles in Bi_2Sr_2CaCu_2O_8 studied by angle-resolved photoemission spectroscopy"J. Phys. Chenm. Solids. 60. 1069-1072 (2002)
[Publications] H.Matsui: "High-resolution photoemission study of FeSr_2YCu_2O_<7+δ>"J. Phys. Chem. Solids. 63. 2329-2332 (2002)
[Publications] T.Takahashi: "Progress of high-resolution photoemission spectroscopy in strongly correlated electron systems"Surface Review and Letters. 9. 995-1006 (2002)
[Publications] H.Kumigashira: "Hybridization gap in Kondo insulators CeRhSb and CeRhAs studied by ultrahigh-resolution photoemission spectroscopy"Physica B. 312-313. 208-209 (2002)
[Publications] H.Kumigashira: "Resonant angle-resolved photoemission study of heavy fermion material CeRu_2Si_2"Physica B. 312-313. 658-659 (2002)
[Publications] T.Ito: "Ultrahigh-resolution angle-resolved photoemission spectroscopy of UPd_3"Physica B. 312-313. 653-654 (2002)
[Publications] S.Souma: "Direct observation of pseudo-gap of SmB_6 using ultrahigh-resolution photoemission spectroscopy"Physica B. 312-313. 329-330 (2002)
[Publications] S.Souma: "Angle-resolved photoemission spectroscopy of Ca_<1-x>La_xB_6"J. Phys. Soc. Jpn.. 72. 317-319 (2002)
[Publications] T.Takahashi: "Angle-resolved photoemission study of novel boride compounds"J. Phys. Soc. Jpn.. 71. 5-10 (2002)
[Publications] A.Chainani: "Electronic structure of black SmS : I 4d-4f resonance and angle-integrated valence-band photoemission spectroscopy"Phvs. Rev. B. 65. 155201-1-7 (2002)
[Publications] T.Ito: "Electronic structure of black SmS : II Angle-resolved photoemission spectroscopy"Phys. Rev. B. 65. 155202-1-4 (2002)
[Publications] T.Sato: "High-resolution angle-resolved photoemission study of BaCo_<1-x>Ni_xS_2"Surface Review and Letters. 9. 1127-1134 (2002)
[Publications] T.Ito: "Ultrahigh-resolution photoemission spectroscopy on UGe_2"J. Phys. Soc. Jpn.. 77. 261-263 (2002)
[Publications] H.Fujisawa: "High-Resolution Angle-Resolved Photoemission Study of η-Mo_4O_<11>"Surface Review and Letters. 9. 1041-1046 (2002)
[Publications] T.Ito: "Band structure of UPd_3 Studied by ultrahigh-resolution angle-resolved photoemission spectroscopy"Phys. Rev. B. 66. 245110-1-6 (2002)
[Publications] S.Souma: "Electronic band structure and Fermi surface of CaB_6 studied by angle-resolved photoemission spectroscopy"Phys. Rev. Lett. 90. 90. 027202-1-027202-4 (2003)
[Publications] H.Matsui: "Systematics of electronic structure and interactions in Bi_2Sr_2Ca_<n-1>Cu_nO_<2n+4>(n=1-3) by angle-resolved photoemission spectroscopy"Phys. Rev. B. 67. 060501R-1-060501R-4 (2003)
[Publications] T.Takahashi: "Direct evidence for superconducting quasiparticle in triple-layered high-T_e superconductor"Physuca C. (in press).

2002 Fiscal Year Annual Research Report

超高分解能光電子分光装置の開発と高温超伝導体準粒子の研究

Principal Investigator

高橋 隆 東北大学, 大学院・理学研究科, 教授 (00142919)

Research Products

[Publications] T.Sato: "Low energy excitation and scalling in Bi_2Sr_2Ca_<n-1>Cu_nO_<2n+4>(n=1-3) : Angle-resolved photoemission spectroscopy"Phys. Rev. Lett.. 89. 067005-1-067005-4 (2002)

[Publications] S.Nishina: "Zn-substitution effects on the low-energy quasiparticles in Bi_2Sr_2CaCu_2O_8 studied by angle-resolved photoemission spectroscopy"J. Phys. Chenm. Solids. 60. 1069-1072 (2002)

[Publications] H.Matsui: "High-resolution photoemission study of FeSr_2YCu_2O_<7+δ>"J. Phys. Chem. Solids. 63. 2329-2332 (2002)

[Publications] T.Takahashi: "Progress of high-resolution photoemission spectroscopy in strongly correlated electron systems"Surface Review and Letters. 9. 995-1006 (2002)

[Publications] H.Kumigashira: "Hybridization gap in Kondo insulators CeRhSb and CeRhAs studied by ultrahigh-resolution photoemission spectroscopy"Physica B. 312-313. 208-209 (2002)

[Publications] H.Kumigashira: "Resonant angle-resolved photoemission study of heavy fermion material CeRu_2Si_2"Physica B. 312-313. 658-659 (2002)

[Publications] T.Ito: "Ultrahigh-resolution angle-resolved photoemission spectroscopy of UPd_3"Physica B. 312-313. 653-654 (2002)

[Publications] S.Souma: "Direct observation of pseudo-gap of SmB_6 using ultrahigh-resolution photoemission spectroscopy"Physica B. 312-313. 329-330 (2002)

[Publications] S.Souma: "Angle-resolved photoemission spectroscopy of Ca_<1-x>La_xB_6"J. Phys. Soc. Jpn.. 72. 317-319 (2002)

[Publications] T.Takahashi: "Angle-resolved photoemission study of novel boride compounds"J. Phys. Soc. Jpn.. 71. 5-10 (2002)

[Publications] A.Chainani: "Electronic structure of black SmS : I 4d-4f resonance and angle-integrated valence-band photoemission spectroscopy"Phvs. Rev. B. 65. 155201-1-7 (2002)

[Publications] T.Ito: "Electronic structure of black SmS : II Angle-resolved photoemission spectroscopy"Phys. Rev. B. 65. 155202-1-4 (2002)

[Publications] T.Sato: "High-resolution angle-resolved photoemission study of BaCo_<1-x>Ni_xS_2"Surface Review and Letters. 9. 1127-1134 (2002)

[Publications] T.Ito: "Ultrahigh-resolution photoemission spectroscopy on UGe_2"J. Phys. Soc. Jpn.. 77. 261-263 (2002)

[Publications] H.Fujisawa: "High-Resolution Angle-Resolved Photoemission Study of η-Mo_4O_<11>"Surface Review and Letters. 9. 1041-1046 (2002)

[Publications] T.Ito: "Band structure of UPd_3 Studied by ultrahigh-resolution angle-resolved photoemission spectroscopy"Phys. Rev. B. 66. 245110-1-6 (2002)

[Publications] S.Souma: "Electronic band structure and Fermi surface of CaB_6 studied by angle-resolved photoemission spectroscopy"Phys. Rev. Lett. 90. 90. 027202-1-027202-4 (2003)

[Publications] H.Matsui: "Systematics of electronic structure and interactions in Bi_2Sr_2Ca_<n-1>Cu_nO_<2n+4>(n=1-3) by angle-resolved photoemission spectroscopy"Phys. Rev. B. 67. 060501R-1-060501R-4 (2003)

[Publications] T.Takahashi: "Direct evidence for superconducting quasiparticle in triple-layered high-T_e superconductor"Physuca C. (in press).

高橋隆東北大学, 大学院・理学研究科, 教授 (00142919)