1991 年度実績報告書

相関の強いフェルミ粒子系とその超伝導・超流動に関する理論的研究

研究課題

研究課題/領域番号	01540296
研究機関	名古屋大学
研究代表者	山田一雄名古屋大学, 教養部, 教授 (10022542)
研究分担者	三宅和正大阪大学, 基礎工学部, 助教授 (90109265) 平島大名古屋大学, 理学部, 助手 (20208820) 松浦民房名古屋大学, 理学部, 助教授 (10022609) 柏村昌平名古屋大学, 教養部, 教授 (80023563)
キーワード	強相関電子系 / 重い電子系 / ク-パ-対とボ-ス凝縮 / 銅酸化物超伝導体 / フェルミ液体論 / ハバ-ド模型 / tーJ模型 / pーd模型
研究概要	強相関電子系に共通の電子の遍歴性と局在性の二重性という特徴をあらわに取り込んだ量子力学的現象論の遍歴・局在双対性理論にもとづいて、重い電子系で観測されているメタ磁性の系統的な性質および弱い反強磁性の起源、更には銅酸化物のノ-マル状態の磁化率の異常が理解できることを示した。銅酸化物導体で観測されるいわゆるmidーgap statesの振舞いをpーdモデルのフェルミ液体理論とGutzwillerの近似的変分法とを組み合わせることにより説明するとともに、超伝導の起源を論じる際にはCuO_2平面の構造を反映した波数依存性をもつ「くりこみ因子」の効果を考慮することが決定的に重要であることを指摘した。また、pーdモデルの電子状態を系統的1/Nー展開の方法で調べた。そのなかで、電荷のゆらぎ感受率はホ-ルの注入にともない転移温度と同様に急激に増大の後減少することが明らかになった。ク-パ-ペア凝縮と「2電子分子」のボ-ス凝縮とのクロスオ-バ-を論じたNozie^^´res&SchmittーRinkの理論(NSR)を二次元系に適用するとき、2次元のゆらぎの特性を反映して低温でのfixed pointとしてSchmittーRink et al.により見つけられた「複合ボゾンのボ-ス凝縮」の他に「フェルミ液体的」なものが存在することを示した。tーJモデルにおけるホ-ルの自由度とスピンの自由度の分離の度合に関して、Jを増大させると分離が悪くなることを見いだした。更に、フラストレ-トした2次元量子スピン系の数値的対角化の研究を行い、フラストレ-ションを強くしてもネ-ル的なスピン秩序が消えないことを見いだした。

研究成果
(19件)

すべてその他

すべて文献書誌 (19件)

[文献書誌] K.Miyake: "ItinerantーLocalized Duality Model for Heavy Fermions and Strongly Correlated Metals" Physica B. 171. 20-29 (1991)
[文献書誌] K.Sano: "The Ground State and Gapless Excitations for a TwoーDimensional Frustrated Antiferromagnet" Journal of the Physical Society of Japan. 60. 3807-3817 (1991)
[文献書誌] I.Doi: "Hole Motion in OneーDimensional tーJーJ^1 Model" Physica B. 165&166. 1025-1026 (1990)
[文献書誌] D.S.Hirashima: "Anomalous Temperature Dependence of the Lower Critical Fields in HighーTemperature Superconductors" Journal of the Physical Society of Japan. 59. 24-27 (1990)
[文献書誌] K.Takano: "Origin of ResonatingーValenceーBond States for a HubbardーType Model" Physical Review B. 39. 7367-7370 (1989)
[文献書誌] Y.O^^~no: "Electronic State of Strongly Correlated Electrons" Physica C. 159. 875-877 (1989)
[文献書誌] I.Doi: "Ground State with Soliton in OneーDimensional tーt^1ーJーJ^1 Model" Physical Review B. 45. 274-284 (1992)
[文献書誌] A.Tokumitu: "Crossover between CooperーPair Condensation and BoseーEinstein Condensation of “DiーDlectronic Molecules"in TwoーDimensional Superconductors" Progress of Theoretical Physics(Supplement). 106. 63-73 (1991)
[文献書誌] A.Tokumitu: "A SelfーConsistent Theory of the Pair Fluctuations in the TwoーDimensional Fermi Superfluidity" Journal of the Physical Society of Japan. 60. 380-383 (1991)
[文献書誌] D.S.Hirashima: "Metal Insulator Transition and Charge Fluctuation in the dーp Model" Journal of the Physical Society of Japan. 60. 2269-2284 (1991)
[文献書誌] D.S.Hirashima: "Charge Fluctuation in the dーp modelーEffects of the Repulsive Interaction between dーand pーHoles" Journal of the Physical Society of Japan. 60. 1864-1868 (1991)
[文献書誌] A.Tokumitu: "Attractive Channel for Cooper pairing with“s"ーSymmetry Driven by the WavenumberーDependent Renormalization of pーand dーelectrons Forming the Fermi Quasiparticles on CuO_2 Plane of HighーT_C Cuprates" Physica C. 185ー189. 1623-1624 (1991)
[文献書誌] I.Doi: "Ground State with Soliton in OneーDimensional tーt^1ーJーJ^1 Model" Physical Review B. 45. 274-284 (1992)
[文献書誌] A.Tokumitu: "Crossover between CooperーPair Condensation and BoseーDinstein Condensation of “DiーElectronic Molecules"in TwoーDimensional Superconductors" Progress of Theoretical Physics(Supplement). 106. 63-73 (1991)
[文献書誌] K.Miyake: "ItinerantーLocoalized Duality Model for Heavy Fermions and Strongly Correlated Metals" Physica B. 171. 20-29 (1991)
[文献書誌] K.Sano: "The Ground State and Gapless Excitations for a TwoーDimensional Frustrated Antiferromagnet" Journal of the Physical Society of Japan. 60. 3807-3817 (1991)
[文献書誌] D.S.Hirashima: "MetalーInsulator Transition and Charge Fluctuation in the dーp Model" Journal of the physical Society of Japan. 60. 2269-2284 (1991)
[文献書誌] D.S.Hirashima: "Charge Fluctuation in the dーp ModelーEffects of the Repulsive Interaction between dーand pーholesー" Journal of the Physical Society of Japan. 60. 1864-1868 (1991)
[文献書誌] K.Miyake: "Relation between Resistivity and Effective Mass in Heavy Fermion and,A15 Compounds" Solid State Communication. 71. 1149-1153 (1989)

1991 年度 実績報告書

相関の強いフェルミ粒子系とその超伝導・超流動に関する理論的研究

研究代表者

山田 一雄 名古屋大学, 教養部, 教授 (10022542)

研究成果

[文献書誌] K.Miyake: "ItinerantーLocalized Duality Model for Heavy Fermions and Strongly Correlated Metals" Physica B. 171. 20-29 (1991)

[文献書誌] K.Sano: "The Ground State and Gapless Excitations for a TwoーDimensional Frustrated Antiferromagnet" Journal of the Physical Society of Japan. 60. 3807-3817 (1991)

[文献書誌] I.Doi: "Hole Motion in OneーDimensional tーJーJ^1 Model" Physica B. 165&166. 1025-1026 (1990)

[文献書誌] D.S.Hirashima: "Anomalous Temperature Dependence of the Lower Critical Fields in HighーTemperature Superconductors" Journal of the Physical Society of Japan. 59. 24-27 (1990)

[文献書誌] K.Takano: "Origin of ResonatingーValenceーBond States for a HubbardーType Model" Physical Review B. 39. 7367-7370 (1989)

[文献書誌] Y.O^^~no: "Electronic State of Strongly Correlated Electrons" Physica C. 159. 875-877 (1989)

[文献書誌] I.Doi: "Ground State with Soliton in OneーDimensional tーt^1ーJーJ^1 Model" Physical Review B. 45. 274-284 (1992)

[文献書誌] A.Tokumitu: "Crossover between CooperーPair Condensation and BoseーEinstein Condensation of “DiーDlectronic Molecules"in TwoーDimensional Superconductors" Progress of Theoretical Physics(Supplement). 106. 63-73 (1991)

[文献書誌] A.Tokumitu: "A SelfーConsistent Theory of the Pair Fluctuations in the TwoーDimensional Fermi Superfluidity" Journal of the Physical Society of Japan. 60. 380-383 (1991)

[文献書誌] D.S.Hirashima: "Metal Insulator Transition and Charge Fluctuation in the dーp Model" Journal of the Physical Society of Japan. 60. 2269-2284 (1991)

[文献書誌] D.S.Hirashima: "Charge Fluctuation in the dーp modelーEffects of the Repulsive Interaction between dーand pーHoles" Journal of the Physical Society of Japan. 60. 1864-1868 (1991)

[文献書誌] A.Tokumitu: "Attractive Channel for Cooper pairing with“s"ーSymmetry Driven by the WavenumberーDependent Renormalization of pーand dーelectrons Forming the Fermi Quasiparticles on CuO_2 Plane of HighーT_C Cuprates" Physica C. 185ー189. 1623-1624 (1991)

[文献書誌] I.Doi: "Ground State with Soliton in OneーDimensional tーt^1ーJーJ^1 Model" Physical Review B. 45. 274-284 (1992)

[文献書誌] A.Tokumitu: "Crossover between CooperーPair Condensation and BoseーDinstein Condensation of “DiーElectronic Molecules"in TwoーDimensional Superconductors" Progress of Theoretical Physics(Supplement). 106. 63-73 (1991)

[文献書誌] K.Miyake: "ItinerantーLocoalized Duality Model for Heavy Fermions and Strongly Correlated Metals" Physica B. 171. 20-29 (1991)

[文献書誌] K.Sano: "The Ground State and Gapless Excitations for a TwoーDimensional Frustrated Antiferromagnet" Journal of the Physical Society of Japan. 60. 3807-3817 (1991)

[文献書誌] D.S.Hirashima: "MetalーInsulator Transition and Charge Fluctuation in the dーp Model" Journal of the physical Society of Japan. 60. 2269-2284 (1991)

[文献書誌] D.S.Hirashima: "Charge Fluctuation in the dーp ModelーEffects of the Repulsive Interaction between dーand pーholesー" Journal of the Physical Society of Japan. 60. 1864-1868 (1991)

[文献書誌] K.Miyake: "Relation between Resistivity and Effective Mass in Heavy Fermion and,A15 Compounds" Solid State Communication. 71. 1149-1153 (1989)

1991 年度実績報告書

山田一雄名古屋大学, 教養部, 教授 (10022542)