1998 Fiscal Year Annual Research Report

スピノ-電荷-光・結合系の相制御

Research Project

Project/Area Number	08CE2003
Research Institution	The University of Tokyo
Principal Investigator	宮野健次郎東京大学, 大学院・工学系研究科, 教授 (90167677)
Co-Investigator(Kenkyū-buntansha)	鹿野田一司東京大学, 大学院・工学系研究科, 教授 (20194946) 内田慎一東京大学, 大学院・工学系研究科, 教授 (10114399) 十倉好紀東京大学, 大学院・工学系研究科, 教授 (30143382) 永長直人東京大学, 大学院・工学系研究科, 教授 (60164406) 内野倉国光東京大学, 大学院・工学系研究科, 教授 (20015564)
Keywords	スピン-電荷-光結合系 / 光誘起相転移 / 強相関電子系 / モット絶縁体 / 量子スピン系 / 酸化物エレクトロニクス / 巨大磁気抵抗効果 / 場の理論
Research Abstract	本研究の目的は、いわゆる強相関電子系の学理を解明し、これを工学に応用するための基礎をつくることである。この系においては電子の持つスピン、電荷、軌道の自由度が、互いに強く相互作用しあうことによって極めて複雑な相転移を起こす。本研究では電場や磁場のような従来型の外場のみならず、特に光を用いた相制御を企図している。 1, スピン-電荷結合系の光による相制御:(1)光によって相転移を誘起することは本研究の中心課題である。pr_<1-x>Ca_xMnO_3(X=0.1-0.5)において光誘起-絶縁体・金属(IM)転移を観測した。これにより、この現象が電荷整列相に限らないモット絶縁体一般の光誘起金属転移であることを確認した。また、逆の転移過程の時間分解測定を行い、基底絶縁体状態の安定性の違いを測定した。(2)層状酸化物La_<0.5>sr_<1.5>MnO_4において、複屈折法を用いて軌道整列を光検出した。(3)2次元構造をもつ二重交換系強磁性体である(La,Sr)_3Mn_2O_7において基底状態の強磁性金属相においても中赤外領域にピーク構造を持つ光学スペクトルが得られ、キャリアのダイナミクスが極めてインコヒーレントであることを明らかにした。(4)6種類の銅酸化物絶縁体について、電荷移動励起に伴う中赤外域での強い過渡誘導吸収が観測された。その温度特性、時間応答特性は銅・酸素構造の次元性に強く依存することがわかった。 2. スピン-電荷結合系のスピニクス:(1)La系高温超伝導体において、ピン止め中心を導入することで不整合スピン・電荷秩序状態が安定化することを観測し、高温超伝導の長年の謎であった1/8問題の解明に一歩近づいた。また、ドープされた正孔のスピンと電荷が空間分離しCUO_2面上でストライプ状の秩序(CDW/SDW)を形成することを明らかにした。(2)一次元スピン梯子系Sr_<14>Cu_<24>O_<41>、の単結晶においてCa置換により正孔が梯子にドーピングされていることを実証するとともに、正孔が対を組み梯子上を運動すること、そして低温では正孔対が電荷整列(CDW形成)して局在することを見出した。(3)不純物ドープしたCuGeo_3におけるスピンパイエルス状態と反強磁性状態の共存問題を明らかにするため種々の測定を行った。特に、純粋系では反強磁性相は存在しないが、0.1%のZn置換により 0.03K付近で反強磁性相が生じることを見出した。(4)これまで高温超伝導体のみでしか確認されていなかったジョセフソン・プラズマ共鳴を有機超伝導体で始めて確認した。類以物質において磁束の位相コヒーレンスが大きく変化する境界があり、局所磁化の跳びを伴う磁束格子の1次転移(デカップリング転移)であることを明らかにした。(5)二量体分子性物質系κ-(BEDT-TTF)_2Cu[N(CN)_2]Brを重水素置換することにより、超伝導からモット絶縁相に至る相制御に成功し、モット転移近傍での電子有効質量の増大がないことを示した。また、冷却速度により超伝導相と絶縁体相の間を可逆的に相変換できることも示した。(6)ハロゲン架橋Ni錯体を種々合成するとともに、光励起状態の性質を調べ、特に、10^<-6>esuに及ぶ強い3次非線型光学効果を示すことを明らかにした。一次元の銅酸化物でも同様に大きな非線型光学効果が見られ、強相関一次元系に共通の現象であることが明らかとなった。 3. スピン-電荷-光・結合系の量子論と強相関エレクトロニクスの原理:(1)Mn酸化物の相図を平均場近似で調べ、軌道モーメントの生成が実験で得られた相図を再現するために不可欠であることを示した。さらに揺らぎの効果をRPA近似で調べ、スピン波分散を中性子散乱実験と比較した。(2)Ru酸化物のp-波超伝導と強磁性に対しSO(5)の対称性に基づく有効理論を提唱し、準古典近似で集団励起モードを調べた。(3)強相関系の基底・励起状態に対する電子構造計算のために、GW法を定式化、Niについて適用している。(4)LDA+U法をMn系ペロブスカイトNd_<1-x>Sr_xMnO_3に適用し、x=0.4〜0.6の範囲で電子構造を調べ、磁気、軌道秩序状態が実験結果と良く一致した。また磁気および軌道秩序構造と格子歪みの関係を、フルポテンシャルLSDA+U法を用いて調べた。

Research Products

(99 results)

All Other

All Publications (99 results)

[Publications] H.Aubin: "Quasparticles and Thermal Conductivity" Scicence. 280. 11a (1998)
[Publications] R.Yamada: "Pressure effect on the vortex phase diagram in Bi_2Sr_2CaCu_2O_<8+y>" Rev.High Pressure Sci Technol.7. 511-514 (1998)
[Publications] T.Tamegai: "Vortex phase diagram in heavy-ion irradiated Bi_2Sr_2CaCu_2O_<8+y> studied by Josephson plasma resonance." Advance in Superconductivity. X. 473-476 (1998)
[Publications] S.J.Bending: "Vortex lattice "melting in BSCCO(2212) single crystals;insights from scanning Hall probe microscopy" Advances in Superconductivity. X. 401-404 (1998)
[Publications] T.Shibauchi: "Vortex-lattice phase transition in the wuasi-dimensional organic superconductor." Advances in Supercondictivity. X. 453-456 (1998)
[Publications] 永長直人: "複合フェルミオンとゲージ場" 固体物理. 34(5). (1999)
[Publications] D.T.Fuchs: "Transport properties governed by surface barriers in Bi_2Sr_2CaCu_2O_8" Nature. 391. 373-376 (1998)
[Publications] A.Oral: "Direct observation of melting of the vortex solid in Bi_2Sr_2CaCu_2O_<8+y> single crytals" Phys.Rev.Lett.80. 3610-3613 (1998)
[Publications] D.T.Fuchs: "Possible new vortex matter phases in Bi_2Sr_2CaCu_2O_8" Phys.Rev.Lett.80. 4871-4974 (1998)
[Publications] S.Ooi: "Evolution of vortex phase diagram with oxygen-doping in Bi_2Sr_2CaCu_2O_<8+y>" Physica. C302. 339-345 (1998)
[Publications] R.A,Doyle: "Role of sample geometry on nonlinear transport properies of the vortex solid in Bi_2Sr_2CaCu_2O_8" Phys.Rev.B58. 135-138 (1998)
[Publications] R.A.Doyle: "The Effect of sample shape on the magnetization in Bi_2Sr_2CaCu_2O_<8+δ> crystals" Physica. C308. 123-131 (1998)
[Publications] D.T.Fuchs: "Transport properties of Bi_2Sr_2CaCu_2O_8 crystals with and without surface barries." Phys.Rev.Lett.81. 3944-3947 (1998)
[Publications] H.Enriquez: "Vortex-lattice melting phase slips.and decoupling studied by microwave dissipation in Bi_2Sr_2CaCu_2O_<8+δ>" Phys.Rev.Lett.B58. R14745-14748 (1998)
[Publications] H.Aubin: "Evidence for field-induced excitation in low-temperature thermal conductivity of Bi_2Sr_2CaCu_2O_8" Phys.Rev.Lett.82. 624-627 (1999)
[Publications] K,Imura: "Quantum Transport in γ=2/3 spin-single quantum Hall edges." Phys.Rev.B57(12). R6826-6829 (1998)
[Publications] N.Nagaoka: "Lattice Instability in the Spin-Ladder System under Magnetic Field." J.Phys.Soc.Jpn.67(6). 1876-1878 (1998)
[Publications] N.Nagaoka: "Magnetoresistance in Half-Filed Landau Level" J.Phys.Sco.Jpn.67(10). 3353-3355 (1998)
[Publications] R.Maezono: "Phase Diagram in Mangense Oxides" Phys.Rev.B58. 11583-11596 (1998)
[Publications] V.Ponomarenko: "Transport through a ID Mott-Hubbard Insulater of finite Length" Phys.Rev.Lett.81(11). 2304-2307 (1998)
[Publications] S.Murakami: "An SO(5) model of p-wave superconductivity and ferromagnetism" to appear in Phys.Rev.Lett.(1999)
[Publications] V.Ponomarenko: "On Interaction Induced Renormalization in ID Transport" to appear in Solid State Commun.(1999)
[Publications] F.Goehmann: "Fermionic reoresebtations of intergrable lattice systems." J.Phys.A31. 7729-7749 (1998)
[Publications] T.Morinari: "Quantum Hall effect half-filled landau Level:Pairing of composite fermions" Phys.Rev.Lett.81. 3741-3744 (1998)
[Publications] T.Morinari: "Composite-fermion pairing in bilayer quantum Hall systems" to be published in Phys.Rev.B.
[Publications] K,-I.Imura: "Tunneling in Paired fractional quantum Hall states:conductance and Andreev reflection of non-Abelians" Solid State Commun.107. 497-502 (1998)
[Publications] K.-I.Imura: "Quantum transport in fractional quantum Hall edges" Physica. B249-251. 420-425 (1998)
[Publications] K,-I.Imura: "Quantum transport in spin-singletγ=2/3 edges" Physica. B256-258. 125-129 (1998)
[Publications] K,Fischer: "Absence of two energy scales in the two-impurity Kondo model" Phys.Rev.B57(12). R6771-6774 (1998)
[Publications] T.Boeske: "Cu-O network-dependent core-hole screening in low-dimensional cuptate systems:A high-resolution x-ray photoemission study" Phys.Rev.B57. 138-141 (1998)
[Publications] M.Takigawa: "Spin and charge dynamics in the hole-doped one-dimensional-chain-ladder composite material Sr_<14>Cu_<24>O_<41> Cu NMR/NQR studies" Phys.Rev.B57. 1124-1140 (1998)
[Publications] B.Nachimu: "Reply to comment by C.Bernhard" Phys.Rev.Lett. 80. 206 (1998)
[Publications] S.Haffner: "Unccupied electronic structure of Sr_2CuO_2Cl_2 and Ba_2Cu_3O_4Cl_2 :Experiment and theory" Phys.Rev.B57. 3672-3678 (1998)
[Publications] Y,Mizuno: "Elcetronic states and magnetic prooerties of edge-sharing Cu-o chains" Phys.Rev.B57. 5326-5335 (1998)
[Publications] R.Henn: "Far infrared ellipsometry using synchrotron radiation : the out-of-plane response of La_<2-x>Sr_xCuO_4" Thin Solid Films. 313-314. 642-648 (1998)
[Publications] T.Nakanishi: "High-Pressure Transport Properties of the Superconducing Spin-Ladder System Sr_<14-x>Ca_xCu_<24>O_<41+δ>" J.Phys.Soc,Jpn.67. 2408-2414 (1998)
[Publications] M.Boehm: "Copeting exchange interactions in Li_2CuO_2" Europhys.Lett.43. 77-82 (1998)
[Publications] R,Neudert: "Manifestation of Spin-Charge Separation in the Dynamic Dielectric Response of One-Dimensional Sr_2CuO_3" Phys.Rev.Lett.81. 657-660 (1998)
[Publications] T.Nagata: "Pressure-Induced Dimensional Crossover and Superconductivity in the Hole-Doped Two-Leg ladder Compund Sr_<14-x>Ca_xcu_<24>O_<41>" Phys.Rev.Lett.81. 1090-1093 (1998)
[Publications] R.S,Eccleston: "Spin Dynamices of the Spin-Ladder Dimer-Chain Material Sr_<14>Cu_<24>O_<41>" Phys.Rev.Lett.81. 1702-1705 (1998)
[Publications] A.Ino: "Doping Dependent Density of Stataes and Pseudogap Behavior in La_<2-x>Sr_xCuO_4" Phys.Rev.Lett.81. 2124-2127 (1998)
[Publications] O,V.Misochiko: "Low energy Raman continua of La_<2-x>Sr_<>CuO_4 high Tc superconductors : polarization,doping and temperature dependences." Phys.Lett.248. 423-430 (1998)
[Publications] A.Fujimori: "Chemical Potential Shift,Density of States and Fermi Surfaces in Overdoped and Underdoped La_<2-x>sr_4CuO_4" J.Phys.Chem.Solids. 59. 1892-1896 (1998)
[Publications] S.Tajima: "Far-infraed Charge Response of Spin/Charge Stripe Order Phase in (La,Nd,Sr)_2CuO_4" J.Phys.Chem.Solids. 59. 2015-2017 (1998)
[Publications] B.Nachumi: "Muon spin relaxation study of the stripe pahse order in La_<1.6-x>Nd_<0.4>Sr_2CuO_4 and related 214 cuprates" Phys.Rev.B58. 8760-8772 (1998)
[Publications] A.Fujimori: "Chemical potential shifts in correlated systems studied by photoemisson spectroscopy." Phys.Rev,Lett.82. 1313-1316 (1998)
[Publications] J.O.Li: "Structural properties and charge-ordering transition in LaSr_2Mn_2O_7" Phys.Rev.B57. R3205-R3208 (1998)
[Publications] K,Yamamoto: "Raman scattering of the charge-spin stripes in La_<1.67>Sr_<0.33>NiO_4" Phys,Rev,Lett.80. 1493-1496 (1998)
[Publications] M.Tokunaga: "High-magnetic-field study of the phase transitions of R_<1-x>Ca_xMnO_3(R=Pr,Nd)" Phys.Rev.B57. 5259-5264 (1998)
[Publications] Y.Murakami: "Direct observation of charge and orbital ordering in La_<0.5>Sr_<1.5>MnO_4" Phys.Rev.Lett.80. 1932-1935 (1998)
[Publications] T.Ishikawa: "Optical probe of anisotropic and incoherent charge dynamics in a layered ferromagnet : La_<1.2>Sr_<1.8>Mn_2O_7" Phys.Rev.B57. R8079-R8082 (1998)
[Publications] Y.Okimoto: "Charge ordering and disordering transitions in Pr_<1-x>Ca_xMnO_3 (x=0.4)as investigated by optical spectroscopy." Phys.Rev.B57. 9377 (1998)
[Publications] Y.Tokura: "Thermally-induced insulator-metal taransition in LaCoO_3 : a view based on Mott transition" Phys.Rev.B68. R1699-R1702 (1998)
[Publications] A.Asamitsu: "Hall effect in La_<1-x>Sr_xMnO_3" Phys.Rev.B58. 47-50 (1998)
[Publications] S.Yamaguchi: "Magneto-optical Kerr effects in perovskite-type transition-metal oxides : La_<1-x>Sr_xMnO_3 and La_<1-x>Sr_xCoO_3" Phys.Rev.D58. 6862-6870 (1998)
[Publications] M.Fiebig: "Visualzation of the local insulator-metal transition in Pro_<0.7>Ca_<0.3>MnO_3" Science. 280. 1925-1928 (1998)
[Publications] K.Ogawa: "Stability of photoinduced insulator-metal transition in Pr_<1-x>Ca_xMnO_3" Phys.Rev.B57. R15033-15036 (1998)
[Publications] Y,Murakami: "Resonant x-ray scattering from orbital ordering in laMn_3" Phys,Rev.Lett.81. 582-585 (1998)
[Publications] Y.Tokura: "Spin-coupled charge dynamics in layered manganite crystals" J.Korean Phys.Sci.33. 168-173 (1998)
[Publications] H.Yoshizawa: "Anisotropic spin waves in a metallic antiferromgnet Nd_<0.45>Sr_<0.55>MnO_3" Phys.Rev.B58. R571-574 (1998)
[Publications] R.H.Heffner: "Effects of readece.dimensionally on spin dyanamic in the layerd perovskit La_<1-4>Sr_<1-6>Mn_2O_7" Phys. Rev.letter. 81. L571-574 (1998)
[Publications] R,H,Heffner: "Effect of reduced dimensionality on spin dynaics in the layered perovskite La_<1.4>Sr_<1.6>Mn_nO_7" Phys.Rev.Lett.81. 1706-1709 (1998)
[Publications] S.K.Park: "Charge-gap fromation upon the Verywey transition in Fr_3O_4" Phys.Rev.B58. 3717-3720 (1998)
[Publications] D.S,Dessau: "K-deoebdent electronic structure, a large "ghost"fermi surface,and pseudogap in a layerd magenerotorisedsrte" Phys.Rev.lett.in press.
[Publications] K,I,Kobayashi: "Room-temperature magnetorestistance in an oxides material" Nature. 395. 677-680 (1998)
[Publications] M.Izumi: "Atoically defined epitaxy and physical propertied of strained La_<0.6>Sr_<0.4>MnO_3 films" Appl.Phys.Lett. 73. 2497-2499 (1998)
[Publications] T.Okuda: "Critical behavior of metal-insulator transition in La_<1-x>Sr_xMnO_3" Phys.Rev.Lett.81. 2497-2499 (1998)
[Publications] T.Okuda: "Critical behavior of metal-insulator transition in La_<1-x>Sr_xMnO_7" Phys.Rev.Lett.81. 3203-3206 (1998)
[Publications] T.Kimura: "Successive structural transitions coupled with magnetotransport properties properries in LaSr_2Mn_2O_7" Phys.Rev.B58. 11081-1108 (1998)
[Publications] T.Ishikawa: "Optical spectroscopy of charge-order transition in La_<1/3>Sr_</3>MnFeO_3" Phys.Rev. B58. R13326-R13329 (1998)
[Publications] A.V Puchkov: "ARPES results on Sr_22RuO_4 : fermi surface revistied" Phys.Rev.B58. R13322-R13325 (1998)
[Publications] Y.Konishi: "Fabrication and physical propentoes of c-axis oriented thin film oflayered perovsaite La_<1-x>Sr_xMnO_3" Appl.Phys.Lett.73. 3004-3006 (1998)
[Publications] R.Kumai: "Band-filling control of π-d electron system based on bis(ethlylendithio) tetrathiafulcalene cation radical salts" J.American Chem.Soc.120. 8263-8264 (1998)
[Publications] S.Horiuchi: "Chemical control of ferroelectric neutral-ionic ransition in charge0trabsfer complexes TTF_<1-x>TSF_xQC_<14>" International Workshop on Non-Accelerator New Physics(NANP-97). 120. 7379-7380 (1998)
[Publications] T.Kimura: "Anisotripic magbetiekastic phenomena in layerd manganite crystals: Implication of charge in orbital state" Phys.Revv,Lett.81. 5920-5923 (1998)
[Publications] T.G.Perring: "Ordered stack of spin valves in a layered magnetoresistive perovskite" Phys.Rev.B58. R14693-R14696 (1998)
[Publications] K,Kumagai: "Microscopically homogeneous magnetic structure of La_<1-x>Sr_xMnO_3 beyond the range of 0【reverse surface chemistry arrow】x【reverse surface chemistry arrow " Phys.Rev.B59. 97-99 (1999)
[Publications] N.Hosaka: "Photoinduced phase transformation in polythiopene" Phys,Rev.Lett.82. 1672-1675 (1999)
[Publications] M.Imada: "Metal-insulator ransitions" Rev.Mod,Phys.70. 1039-1263 (1998)
[Publications] S.Horiuchi: "Effect of chemical doping on ferroelectric neutral-ionic phase transiton in tetrathiafulvalene-p-chlorani1" Phys.Rev.B. in press.
[Publications] H.Kuwahara: "Two-dimensional charge-transport and spin-valve effect in layered antiferromagnet Nd_<0.45>Se_<0.55>MnO_3" Phys.Rev.lett.in press.
[Publications] T.Manako: "Epitaxial thin films of half metallic ordered double perovskite Sr_2FeMoO_6" Appl.Phys.Lett.in press.
[Publications] Y.Tokura: "Optical and magnetic properties of transition metal oxides,Current Opinion." Solid state and materials science. 3. 175-180 (1998)
[Publications] 村上洋一: "層状ペロブスカイト型マンガン酸化物ので電荷・気道秩序の直接観測" 放射熱. 11. 30-37 (1998)
[Publications] 十倉好紀: "磁場で絶縁体が金属に" バリティ. 13. 46-51 (1998)
[Publications] 朝光敦: "超巨大磁気抵抗効果を発現するMn酸化物の物性と相制御" 金属学会報「まてりあ」. 37-4. 254-260 (1998)
[Publications] S.Roche: "Fermi Surface and Temperature Dependence of Conductivity in Qasicrystals." Phys.Rev.B58. 11338-11344 (1998)
[Publications] S.Roche: "Invertigation of quantum transport by meeansn of means of 0(N) real space methos." Phys.Rev.B58. 2284-2291 (1998)
[Publications] T.Fujiwara: "Spin and Orbital Ordering of Nd_<1-x>Sr_xMnO_3 from LDA+U calculations." Phys.Rev.B59 to published. (1999)
[Publications] S.Roche: "Effect of magnetic filed and disorder on electronic properties of carbon manotubes" Phys.Rev.B59. 5242-5246 (1999)
[Publications] K.Kojima: "Search for magnetic order in undoped and doped spin gap systems by μSR." Hyperfine Interactions. 104. 37-42 (1998)
[Publications] A.Zheludev: "Field-induced incommensurate-to-commensurate transition in Ba_2CuGe_2O_7" Phys.Rev.B57. 2968-2978 (1998)
[Publications] K.Hirota: "Magnetic exciations in the Si doped spin-Peierls compound CuGe_<1-x>Si_xO_3" J.Phys.Soc,Jpn.67. 645-650 (1998)
[Publications] T.Sekine: "Spin-Peierls gap and two-magnetic-excitation bound and resonant states in Cu_<1-x>Zn_xGeO_3 and CuGe_<1-y>Si_yO_3" J.Phys.Soc.Jpn.67. 1440-1450 (1998)
[Publications] H.Nojiri: "Exchange splitting in CuGeO_3 under ultra-high magnetic fields" J.Phys.Soc.Jpn.B57. 10276-10279 (1998)
[Publications] T.Tsukada: "Surface flatness and atructure of the bc-cleaved blance of spin-Peierls material CuGo_3" Phys.Rev.B57. 11927-11930 (1998)
[Publications] T.Masuda: "Phase transition between dimerized-antiferromagnetic and uniform-antiferromagnetic phases in unoyrity-doped spin-Peierls cuprate CuGeO_3" Phys.Rev.Lett.80. 4566-4569 (1998)
[Publications] K.Manabe: "Antferromagnetic long-range order in Cu_<1-x>Zn_xGeO_3 with extremely low Zn concentrations" Phys.Rev. B58. R575-578 (1998)
[Publications] 十倉好紀: "電流・光で金属に変わる磁性体" 化学と工業. 51. 908-911 (1998)

1998 Fiscal Year Annual Research Report

スピノ-電荷-光・結合系の相制御

Principal Investigator

宮野 健次郎 東京大学, 大学院・工学系研究科, 教授 (90167677)

Research Products

[Publications] H.Aubin: "Quasparticles and Thermal Conductivity" Scicence. 280. 11a (1998)

[Publications] R.Yamada: "Pressure effect on the vortex phase diagram in Bi_2Sr_2CaCu_2O_<8+y>" Rev.High Pressure Sci Technol.7. 511-514 (1998)

[Publications] T.Tamegai: "Vortex phase diagram in heavy-ion irradiated Bi_2Sr_2CaCu_2O_<8+y> studied by Josephson plasma resonance." Advance in Superconductivity. X. 473-476 (1998)

[Publications] S.J.Bending: "Vortex lattice "melting in BSCCO(2212) single crystals;insights from scanning Hall probe microscopy" Advances in Superconductivity. X. 401-404 (1998)

[Publications] T.Shibauchi: "Vortex-lattice phase transition in the wuasi-dimensional organic superconductor." Advances in Supercondictivity. X. 453-456 (1998)

[Publications] 永長直人: "複合フェルミオンとゲージ場" 固体物理. 34(5). (1999)

[Publications] D.T.Fuchs: "Transport properties governed by surface barriers in Bi_2Sr_2CaCu_2O_8" Nature. 391. 373-376 (1998)

[Publications] A.Oral: "Direct observation of melting of the vortex solid in Bi_2Sr_2CaCu_2O_<8+y> single crytals" Phys.Rev.Lett.80. 3610-3613 (1998)

[Publications] D.T.Fuchs: "Possible new vortex matter phases in Bi_2Sr_2CaCu_2O_8" Phys.Rev.Lett.80. 4871-4974 (1998)

[Publications] S.Ooi: "Evolution of vortex phase diagram with oxygen-doping in Bi_2Sr_2CaCu_2O_<8+y>" Physica. C302. 339-345 (1998)

[Publications] R.A,Doyle: "Role of sample geometry on nonlinear transport properies of the vortex solid in Bi_2Sr_2CaCu_2O_8" Phys.Rev.B58. 135-138 (1998)

[Publications] R.A.Doyle: "The Effect of sample shape on the magnetization in Bi_2Sr_2CaCu_2O_<8+δ> crystals" Physica. C308. 123-131 (1998)

[Publications] D.T.Fuchs: "Transport properties of Bi_2Sr_2CaCu_2O_8 crystals with and without surface barries." Phys.Rev.Lett.81. 3944-3947 (1998)

[Publications] H.Enriquez: "Vortex-lattice melting phase slips.and decoupling studied by microwave dissipation in Bi_2Sr_2CaCu_2O_<8+δ>" Phys.Rev.Lett.B58. R14745-14748 (1998)

[Publications] H.Aubin: "Evidence for field-induced excitation in low-temperature thermal conductivity of Bi_2Sr_2CaCu_2O_8" Phys.Rev.Lett.82. 624-627 (1999)

[Publications] K,Imura: "Quantum Transport in γ=2/3 spin-single quantum Hall edges." Phys.Rev.B57(12). R6826-6829 (1998)

[Publications] N.Nagaoka: "Lattice Instability in the Spin-Ladder System under Magnetic Field." J.Phys.Soc.Jpn.67(6). 1876-1878 (1998)

[Publications] N.Nagaoka: "Magnetoresistance in Half-Filed Landau Level" J.Phys.Sco.Jpn.67(10). 3353-3355 (1998)

[Publications] R.Maezono: "Phase Diagram in Mangense Oxides" Phys.Rev.B58. 11583-11596 (1998)

[Publications] V.Ponomarenko: "Transport through a ID Mott-Hubbard Insulater of finite Length" Phys.Rev.Lett.81(11). 2304-2307 (1998)

[Publications] S.Murakami: "An SO(5) model of p-wave superconductivity and ferromagnetism" to appear in Phys.Rev.Lett.(1999)

[Publications] V.Ponomarenko: "On Interaction Induced Renormalization in ID Transport" to appear in Solid State Commun.(1999)

[Publications] F.Goehmann: "Fermionic reoresebtations of intergrable lattice systems." J.Phys.A31. 7729-7749 (1998)

[Publications] T.Morinari: "Quantum Hall effect half-filled landau Level:Pairing of composite fermions" Phys.Rev.Lett.81. 3741-3744 (1998)

[Publications] T.Morinari: "Composite-fermion pairing in bilayer quantum Hall systems" to be published in Phys.Rev.B.

[Publications] K,-I.Imura: "Tunneling in Paired fractional quantum Hall states:conductance and Andreev reflection of non-Abelians" Solid State Commun.107. 497-502 (1998)

[Publications] K.-I.Imura: "Quantum transport in fractional quantum Hall edges" Physica. B249-251. 420-425 (1998)

[Publications] K,-I.Imura: "Quantum transport in spin-singletγ=2/3 edges" Physica. B256-258. 125-129 (1998)

[Publications] K,Fischer: "Absence of two energy scales in the two-impurity Kondo model" Phys.Rev.B57(12). R6771-6774 (1998)

[Publications] T.Boeske: "Cu-O network-dependent core-hole screening in low-dimensional cuptate systems:A high-resolution x-ray photoemission study" Phys.Rev.B57. 138-141 (1998)

[Publications] M.Takigawa: "Spin and charge dynamics in the hole-doped one-dimensional-chain-ladder composite material Sr_<14>Cu_<24>O_<41> Cu NMR/NQR studies" Phys.Rev.B57. 1124-1140 (1998)

[Publications] B.Nachimu: "Reply to comment by C.Bernhard" Phys.Rev.Lett. 80. 206 (1998)

[Publications] S.Haffner: "Unccupied electronic structure of Sr_2CuO_2Cl_2 and Ba_2Cu_3O_4Cl_2 :Experiment and theory" Phys.Rev.B57. 3672-3678 (1998)

[Publications] Y,Mizuno: "Elcetronic states and magnetic prooerties of edge-sharing Cu-o chains" Phys.Rev.B57. 5326-5335 (1998)

[Publications] R.Henn: "Far infrared ellipsometry using synchrotron radiation : the out-of-plane response of La_<2-x>Sr_xCuO_4" Thin Solid Films. 313-314. 642-648 (1998)

[Publications] T.Nakanishi: "High-Pressure Transport Properties of the Superconducing Spin-Ladder System Sr_<14-x>Ca_xCu_<24>O_<41+δ>" J.Phys.Soc,Jpn.67. 2408-2414 (1998)

[Publications] M.Boehm: "Copeting exchange interactions in Li_2CuO_2" Europhys.Lett.43. 77-82 (1998)

[Publications] R,Neudert: "Manifestation of Spin-Charge Separation in the Dynamic Dielectric Response of One-Dimensional Sr_2CuO_3" Phys.Rev.Lett.81. 657-660 (1998)

[Publications] T.Nagata: "Pressure-Induced Dimensional Crossover and Superconductivity in the Hole-Doped Two-Leg ladder Compund Sr_<14-x>Ca_xcu_<24>O_<41>" Phys.Rev.Lett.81. 1090-1093 (1998)

[Publications] R.S,Eccleston: "Spin Dynamices of the Spin-Ladder Dimer-Chain Material Sr_<14>Cu_<24>O_<41>" Phys.Rev.Lett.81. 1702-1705 (1998)

[Publications] A.Ino: "Doping Dependent Density of Stataes and Pseudogap Behavior in La_<2-x>Sr_xCuO_4" Phys.Rev.Lett.81. 2124-2127 (1998)

[Publications] O,V.Misochiko: "Low energy Raman continua of La_<2-x>Sr_<>CuO_4 high Tc superconductors : polarization,doping and temperature dependences." Phys.Lett.248. 423-430 (1998)

[Publications] A.Fujimori: "Chemical Potential Shift,Density of States and Fermi Surfaces in Overdoped and Underdoped La_<2-x>sr_4CuO_4" J.Phys.Chem.Solids. 59. 1892-1896 (1998)

[Publications] S.Tajima: "Far-infraed Charge Response of Spin/Charge Stripe Order Phase in (La,Nd,Sr)_2CuO_4" J.Phys.Chem.Solids. 59. 2015-2017 (1998)

[Publications] B.Nachumi: "Muon spin relaxation study of the stripe pahse order in La_<1.6-x>Nd_<0.4>Sr_2CuO_4 and related 214 cuprates" Phys.Rev.B58. 8760-8772 (1998)

[Publications] A.Fujimori: "Chemical potential shifts in correlated systems studied by photoemisson spectroscopy." Phys.Rev,Lett.82. 1313-1316 (1998)

[Publications] J.O.Li: "Structural properties and charge-ordering transition in LaSr_2Mn_2O_7" Phys.Rev.B57. R3205-R3208 (1998)

[Publications] K,Yamamoto: "Raman scattering of the charge-spin stripes in La_<1.67>Sr_<0.33>NiO_4" Phys,Rev,Lett.80. 1493-1496 (1998)

[Publications] M.Tokunaga: "High-magnetic-field study of the phase transitions of R_<1-x>Ca_xMnO_3(R=Pr,Nd)" Phys.Rev.B57. 5259-5264 (1998)

[Publications] Y.Murakami: "Direct observation of charge and orbital ordering in La_<0.5>Sr_<1.5>MnO_4" Phys.Rev.Lett.80. 1932-1935 (1998)

[Publications] T.Ishikawa: "Optical probe of anisotropic and incoherent charge dynamics in a layered ferromagnet : La_<1.2>Sr_<1.8>Mn_2O_7" Phys.Rev.B57. R8079-R8082 (1998)

[Publications] Y.Okimoto: "Charge ordering and disordering transitions in Pr_<1-x>Ca_xMnO_3 (x=0.4)as investigated by optical spectroscopy." Phys.Rev.B57. 9377 (1998)

[Publications] Y.Tokura: "Thermally-induced insulator-metal taransition in LaCoO_3 : a view based on Mott transition" Phys.Rev.B68. R1699-R1702 (1998)

[Publications] A.Asamitsu: "Hall effect in La_<1-x>Sr_xMnO_3" Phys.Rev.B58. 47-50 (1998)

[Publications] S.Yamaguchi: "Magneto-optical Kerr effects in perovskite-type transition-metal oxides : La_<1-x>Sr_xMnO_3 and La_<1-x>Sr_xCoO_3" Phys.Rev.D58. 6862-6870 (1998)

[Publications] M.Fiebig: "Visualzation of the local insulator-metal transition in Pro_<0.7>Ca_<0.3>MnO_3" Science. 280. 1925-1928 (1998)

[Publications] K.Ogawa: "Stability of photoinduced insulator-metal transition in Pr_<1-x>Ca_xMnO_3" Phys.Rev.B57. R15033-15036 (1998)

[Publications] Y,Murakami: "Resonant x-ray scattering from orbital ordering in laMn_3" Phys,Rev.Lett.81. 582-585 (1998)

[Publications] Y.Tokura: "Spin-coupled charge dynamics in layered manganite crystals" J.Korean Phys.Sci.33. 168-173 (1998)

[Publications] H.Yoshizawa: "Anisotropic spin waves in a metallic antiferromgnet Nd_<0.45>Sr_<0.55>MnO_3" Phys.Rev.B58. R571-574 (1998)

[Publications] R.H.Heffner: "Effects of readece.dimensionally on spin dyanamic in the layerd perovskit La_<1-4>Sr_<1-6>Mn_2O_7" Phys. Rev.letter. 81. L571-574 (1998)

[Publications] R,H,Heffner: "Effect of reduced dimensionality on spin dynaics in the layered perovskite La_<1.4>Sr_<1.6>Mn_nO_7" Phys.Rev.Lett.81. 1706-1709 (1998)

[Publications] S.K.Park: "Charge-gap fromation upon the Verywey transition in Fr_3O_4" Phys.Rev.B58. 3717-3720 (1998)

[Publications] D.S,Dessau: "K-deoebdent electronic structure, a large "ghost"fermi surface,and pseudogap in a layerd magenerotorisedsrte" Phys.Rev.lett.in press.

[Publications] K,I,Kobayashi: "Room-temperature magnetorestistance in an oxides material" Nature. 395. 677-680 (1998)

[Publications] M.Izumi: "Atoically defined epitaxy and physical propertied of strained La_<0.6>Sr_<0.4>MnO_3 films" Appl.Phys.Lett. 73. 2497-2499 (1998)

[Publications] T.Okuda: "Critical behavior of metal-insulator transition in La_<1-x>Sr_xMnO_3" Phys.Rev.Lett.81. 2497-2499 (1998)

[Publications] T.Okuda: "Critical behavior of metal-insulator transition in La_<1-x>Sr_xMnO_7" Phys.Rev.Lett.81. 3203-3206 (1998)

[Publications] T.Kimura: "Successive structural transitions coupled with magnetotransport properties properries in LaSr_2Mn_2O_7" Phys.Rev.B58. 11081-1108 (1998)

[Publications] T.Ishikawa: "Optical spectroscopy of charge-order transition in La_<1/3>Sr_</3>MnFeO_3" Phys.Rev. B58. R13326-R13329 (1998)

[Publications] A.V Puchkov: "ARPES results on Sr_22RuO_4 : fermi surface revistied" Phys.Rev.B58. R13322-R13325 (1998)

[Publications] Y.Konishi: "Fabrication and physical propentoes of c-axis oriented thin film oflayered perovsaite La_<1-x>Sr_xMnO_3" Appl.Phys.Lett.73. 3004-3006 (1998)

[Publications] R.Kumai: "Band-filling control of π-d electron system based on bis(ethlylendithio) tetrathiafulcalene cation radical salts" J.American Chem.Soc.120. 8263-8264 (1998)

[Publications] S.Horiuchi: "Chemical control of ferroelectric neutral-ionic ransition in charge0trabsfer complexes TTF_<1-x>TSF_xQC_<14>" International Workshop on Non-Accelerator New Physics(NANP-97). 120. 7379-7380 (1998)

[Publications] T.Kimura: "Anisotripic magbetiekastic phenomena in layerd manganite crystals: Implication of charge in orbital state" Phys.Revv,Lett.81. 5920-5923 (1998)

宮野健次郎東京大学, 大学院・工学系研究科, 教授 (90167677)

[Publications] 朝光敦: "超巨大磁気抵抗効果を発現するMn酸化物の物性と相制御" 金属学会報「まてりあ」. 37-4. 254-260 (1998)