2022/08/14 更新

写真a

クリハラ ススム
栗原 進
所属
理工学術院
職名
名誉教授

学歴

  •  
    -
    1976年

    東京大学   工学系研究科   物理工学  

  •  
    -
    1970年

    東京大学   工学部   物理工学科  

学位

  • 東京大学 (日本)   工学博士

  • 東京大学   工学修士

経歴

  • 1996年
    -
     

    早稲田大学理工学部

  • 1985年
    -
    1996年

    NTT基礎研究所

  • 1976年
    -
    1985年

    東京大学物性研究所

所属学協会

  •  
     
     

    American Association for the Advancement of Science

  •  
     
     

    The American Physical Society

  •  
     
     

    物理系学術誌刊行協会

  •  
     
     

    物理系学術誌刊行協会

  •  
     
     

    日本物理学会

  •  
     
     

    米国物理学会 (American Physical Society)

  •  
     
     

    日本物理学会

▼全件表示

 

研究キーワード

  • 巨視的量子現象、超伝導、超流動、Bose-Einstein凝縮、固体物性II(磁性・金属・低温)、物性一般(含基礎論)

論文

  • Collective modes and stability of Bose-Fermi mixtures with a BCS-BEC crossover

    Hiroyuki Shibata, Nobuhiko Yokoshi, Susumu Kurihara

    Physical Review A - Atomic, Molecular, and Optical Physics   75 ( 5 ) 053615  2007年05月

     概要を見る

    We investigate an ultracold Bose-Fermi mixture with a Feshbach resonance between two hyperfine states of fermions. Using a functional integral method, we calculate collective modes associated with fermion pairs and bosons in the superfluid phase. We derive a stability condition of the mixtures that is valid in the entire region of the BCS-BEC crossover. This stability condition, which smoothly connects the well-known results obtained in both the BCS and Bose-Einstein Condensate (BEC) limits, shows that sufficiently strong fermion-boson (FB) interactions destabilize the mixtures. In order to investigate the consequence of this instability, we study the ground-state energy of both the uniformly mixed and the phase-separated states. We find that FB repulsion induces a phase separation, whereas FB attraction should cause a collapse of the mixture. The possibilities for the experimental observation of such instabilities are also discussed. © 2007 The American Physical Society.

    DOI

  • BCS-BEC クロスオーバーを示すボース・フェルミ混合系の集団励起と安定性

    柴田浩行, 余越伸彦, 栗原 進

    Physical Review A   75 ( 5 ) 053615  2007年05月

  • Antiferromagnetism in two-dimensional t-J model: A pseudospin representation

    Daisuke Yamamoto, Susumu Kurihara

    PHYSICAL REVIEW B   75 ( 13 ) 134520  2007年04月

     概要を見る

    We discuss a pseudospin representation of the two-dimensional t-J model. We introduce pseudospins associated with empty sites, deriving a representation of the t-J model that consists of local spins and spinless fermions. We show, within a mean-field approximation, that our representation of t-J model corresponds to the isotropic antiferromagnetic Heisenberg model in an effective magnetic field. The strength and the direction of the effective field are determined by the hole doping delta and the orientation of pseudospins associated with empty sites, respectively. We find that the staggered magnetization in the standard representation corresponds to the component of magnetization perpendicular to the effective field in our pseudospin representation. Using a many-body Green's function method, we show that the staggered magnetization decreases with increasing hole doping delta and disappears at delta approximate to 0.06-0.12 for t/J=2.5-5. Our results are in good agreement with experiments and numerical calculations in contradistinction to usual mean-field methods.

    DOI

  • 2次元t-Jモデルにおける反強磁性:擬スピン表示

    山本大輔, 栗原 進

    Physical Review B   75 ( 13 ) 134520  2007年04月

    DOI

  • Gutzwiller study of spin-1 bosons in an optical lattice under a magnetic field

    T. Kimura, S. Tsuchiya, M. Yamashita, S. Kurihara

    LASER PHYSICS   17 ( 1 ) 54 - 59  2007年01月

     概要を見る

    We study spin-1 bosons in an optical lattice under a magnetic field with the Gutzwiller approximation for the Bose-Hubbard model. Phase boundary curves between superfluids and Mott insulators depend continuously on the magnetic field, and this provides better results than those obtained with the perturbative mean-field approximation. The phase boundary curve as a function of magnetic field has a sharp cusp structure under certain circumstances. In superfluid phases, both the spin magnetizations and fluctuations in the total number of bosons show strong magnetic field dependence, which is related to the fact that both first-and second-order transitions appear on the phase boundary curve according to the magnetic field.

    DOI

  • 磁場下の光学格子中のスピン1ボース粒子系のグッツヴィラー近似による研究

    木村 敬, 土屋俊二, 山下 眞, 栗原 進

    Laser Physics   17   54  2007年

    DOI

  • Superfluid-Mott Insulator Transition of Spin-1 Bosons in an Optical Lattice under a Magnetic Field

    Takashi Kimura, Shunji Tsuchiya, Makoto Yamashita, Susumu Kurihara

    Journal of the Physical Society of Japan   75 ( 7 ) 074601  2006年07月

    DOI

  • 磁場下の光学格子中のスピン1ボース粒子系における超流動-モット絶縁体転移

    木村 敬, 土屋俊二, 山下 眞, 栗原 進

    Journal of the Physical Society of Japan   75 ( 7 ) 074601  2006年07月

  • Spin-charge mixing effects on resonant tunneling in a polarized Luttinger liquid

    K Kamide, Y Tsukada, S Kurihara

    PHYSICAL REVIEW B   73 ( 23 ) 235326  2006年06月

     概要を見る

    We investigate spin-charge mixing effect on resonant tunneling in spin-polarized Tomonaga-Luttinger liquid with double impurities. The mixing arises from Fermi velocity difference between two spin species due to Zeeman effect. Zero bias conductance is calculated as a function of gate voltage V-g, gate magnetic field B-g, temperature, and magnetic field applied to the system. Mixing effect is shown to cause rotation of the lattice pattern of the conductance peaks in (V-g,B-g) plane, which can be observed in experiments. At low temperatures, the contour shapes are classified into three types, reflecting the fact that effective barrier potential is renormalized towards "perfect reflection," "perfect transmission," and magnetic field induced "spin-filtering," respectively.

    DOI

  • 分極したラッティンジャー流体中の共鳴トンネリングに対するスピン・電荷混合効果

    上出健仁, 塚田悠司, 栗原 進

    Physical Review B   73 ( 23 ) 235326  2006年06月

    DOI

  • Phase dependence of phonon tunnelling in bosonic superfluid-insulator- superfluid junctions

    Ippei Danshita, Nobuhiko Yokoshi, Susumu Kurihara

    New Journal of Physics   8   44  2006年03月

     概要を見る

    We consider the tunnelling of phonon excitations across a potential barrier spatially separating two condensates with different macroscopic phases. We analyse the relation between the phase difference φ of the two condensates and the transmission coefficient T by solving the Bogoliubov equations. It is found that T strongly depends on φ, and that the perfect transmission of low-energy excitations disappears when the phase difference reaches the critical value which gives the maximum supercurrent of the condensate. We also discuss the feasibility of observing the phase differences in experiments. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

    DOI

  • Thermal transport properties of a charge density wave 10.1143/jpsj.75.014601

    H Yoshimoto, S Kurihara

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   75 ( 1 ) 014601  2006年01月

     概要を見る

    The effects of collective modes on the thermoelectric properties of a charge density system is studied. We derive the temperature dependences of thermoelectric power and thermal conductivity by applying the linear response theory to the Frohlich Hamiltonian. Energy dissipation has been attributed to the nonlinear interaction between the phase mode and the amplitude mode, ignoring disorder effects. We have found that the temperature dependence of the correlation function between electrical and heat currents is the same as that of the correlation function between electrical currents. This implies that thermoelectric power is inversely proportional to temperature. We have also found that the temperature dependences of all correlation functions are essentially determined by the same mechanism-nonlinear amplitude-phase interaction. The thermal conductivity is nearly constant at a temperature above the amplitude mode gap, and is exponentially low at a temperature sufficiently below it.

    DOI

  • ボース系超流動-絶縁体-超流動接合におけるフォノントンネリングの位相差依存性

    段下一平, 余越伸彦, 栗原 進

    New Journal of Physics   8   44  2006年

  • 電荷密度波系の熱輸送

    吉元広行, 栗原 進

    Journal of the Physical Society of Japan   75 ( 1 ) 014601  2006年01月

    DOI

  • Collective excitations of Bose-Einstein condensates in a double-well potential

    Ippei Danshita, Kyota Egawa, Nobuhiko Yokoshi, Susumu Kurihara

    Journal of the Physical Society of Japan   74 ( 12 ) 3179 - 3185  2005年12月

     概要を見る

    We investigate collective excitations of Bose-Einstein condensates at absolute zero in a double-well trap. We solve the Bogoliubov equations with a double-well trap, and show that the crossover from the dipole mode to the Josephson plasma mode occurs in the lowest energy excitation. It is found that the anomalous tunneling property of low energy excitations is crucial to the crossover. ©2005 The Physical Society of Japan.

    DOI

  • Bosonization approach to the edge reconstruction of two-dimensional electron systems in a quantum dot

    Yanagi, I, S Kurihara

    PHYSICAL REVIEW B   72 ( 24 ) 245337  2005年12月

     概要を見る

    We consider edge reconstruction of electrons in a two-dimensional harmonic trap under a strong magnetic field. In this system the edge reconstruction occurs as a result of competition between electron-electron interaction and confining potential. We develop a bosonization scheme for two-dimensional electron systems. With this method we obtain the excitation spectrum and demonstrate that the edge reconstruction occurs when magnetic field reaches a critical value. We also show that the edge reconstruction depends on the number of electrons. We calculate the third-order terms of bosons in Hamiltonian and examine the effect of those terms with a perturbation theory.

    DOI

  • 量子ドット中の2次元電子系におけるエッジ再構成現象に対するボソン化法アプローチ

    柳 至, 栗原 進

    Physical Review B   72   245337  2005年12月

    DOI

  • 二重井戸中のボース・アインシュタイン凝縮体の集団励起

    段下一平, 江川恭太, 余越伸彦, 栗原 進

    Journal of the Physical Society of Japan   74 ( 12 ) 3179 - 3185  2005年12月

  • Bogoliubov excitations in a Kronig-Penney potential

    Danshita, I, S Kurihara, S Tsuchiya

    PHYSICAL REVIEW A   72 ( 5 ) 053611  2005年11月

     概要を見る

    With use of the Kronig-Penney model, we study the excitation spectrum of a Bose-Einstein condensate in a one-dimensional periodic potential. We solve the Bogoliubov equations analytically and obtain the band structure of the excitation spectrum for arbitrary values of the lattice depth. We find that the excitation spectrum is gapless and linear at low energies, and that it is due to the anomalous tunneling of low-energy excitations, predicted by Kagan et al.

    DOI

  • Kronig-Penney ポテンシャル中のボゴリューボフ励起

    段下一平, 栗原 進, 土屋俊二

    Physical Review A   72   053611  2005年11月

  • マクロな量子コヒーレンス

    栗原 進

    固体物理   40 ( 10 )  2005年10月

  • Spin current through superconductor—Tomonaga Luttinger

    Nobuhiko Yokoshi, Susumu Kurihara

    Physica B   359-361 ( SPEC. ISS. ) 606 - 608  2005年04月

    DOI

  • Zeeman effect on resonant tunneling in spin-polarized Tomonaga-Luttinger liquid

    K Kamide, Y Tsukada, S Kurihara

    PHYSICA B-CONDENSED MATTER   359   645 - 647  2005年04月

     概要を見る

    We investigate spin-charge mixing effect on the resonant tunneling in a spin-polarized Tomonaga-Luttinger liquid, which arises from Fermi velocity differences between two spin species due to Zeeman effect. Zero bias conductance is calculated as a function of gate voltage V-g gate magnetic field B-g, temperature and magnetic field applied to the system. Mixing effect is found to cause deformations of contour shapes of the conductance in (V-g,B-g) plane. At low temperatures, contour shapes are divided into three types; the conductance peaks (1) vanish, (2) form lattices, and (3) form lines. Each corresponds to the phase impurity potential become (1) irrelevant for two spins, (2) relevant for two spins, and (3) relevant for one selective spin. (c) 2005 Elsevier B.V. All rights reserved.

    DOI

  • Bosonization approach to the edge reconstruction in a two-dimensional quantum dot

    Yanagi, I, S Kurihara

    PHYSICA B-CONDENSED MATTER   359   1457 - 1459  2005年04月

     概要を見る

    We consider the edge reconstruction of electrons in a two-dimensional harmonic trap under a strong magnetic field. In this system the edge reconstruction occurs as a result of competition between electron-electron interaction and confining potential. To describe it, we develop a bosonization scheme for two-dimensional electron systems. With this method we obtain the excitation spectrum and confirm that the edge reconstruction occurs when the value of the magnetic field reaches the critical value. We also show that the edge reconstruction depends on the number of electrons too. (c) 2005 Elsevier B.V. All rights reserved.

    DOI

  • Possibility of a first-order superfluid-Mott-insulator transition of spinor bosons in an optical lattice

    T Kimura, S Tsuchiya, S Kurihara

    PHYSICAL REVIEW LETTERS   94 ( 11 ) 110403  2005年03月

     概要を見る

    We study the superfluid-Mott-insulator transition of antiferromagnetic spin-1 bosons in an optical lattice described by a Bose-Hubbard model. Our variational study with the Gutzwiller variational wave function determines that the superfluid-Mott-insulator transition is a first-order one at a part of the phase boundary curve, contrary to the spinless case.

    DOI

  • Josephson

    Nobuhiko Yokoshi, Susumu Kurihara

    Physical Review B   71   104512  2005年03月

  • 超伝導体-Luttinger流体複合系のジョセフソン π 状態

    余越伸彦, 栗原 進

    Physical Review B   71   104512  2005年03月

  • 光学格子上のスピンをもつボソンの超流動-Mott絶縁体一次相転移

    木村 敬, 土屋俊二, 栗原 進

    Physical Review Letters   94   110403  2005年03月

  • Gutzwiller study of spin-1 bosons in an optical lattice

    T Kimura, S Tsuchiya, S Kurihara

    JOURNAL OF LOW TEMPERATURE PHYSICS   138 ( 3-4 ) 651 - 656  2005年02月

     概要を見る

    The antiferromagnetic spin-1 bosons in an optical lattice are studied by the Gutzwiller approximation. We find that the superfluid-Mott insulator transition is of a first-order on a part of the phase boundary.

    DOI

  • 光学格子上のSpin 1ボソンのGutwiller変分法による研究

    木村 敬, 土屋俊二, 栗原 進

    Journal of Low Temperature Physics   138 ( 3-4 ) 651 - 656  2005年02月

    DOI

  • 超伝導-朝永・ラッティンジャー流体接合系を流れるスピン流

    余越伸彦, 栗原 進

    Physica B   359-361   606 - 608  2005年

  • 2次元量子ドットにおけるエッジ・リコンストラクションに対するボソン化法のアプローチ

    柳 至, 栗原 進

    Physica B   359-361   1457 - 1459  2005年

    DOI

  • スピン分極した朝永・ラッティンジャー流体における共鳴トンネルのゼーマン効果

    上出健仁, 塚田悠司, 栗原 進

    Physica B   359-361   645 - 647  2005年

    DOI

  • Superfluid–Mott insulator transition of spin-1 bosons in an optical lattice

    Shunji Tsuchiya, Susumu Kurihara, Takashi Kimura

    Physical Review A   70 ( 4 ) 043628  2004年10月

    DOI

  • マクロな量子トンネリングとコヒーレンス

    栗原 進

    数理科学   42 ( 10 ) 11 - 18  2004年10月

  • Calculation of entropy and specific heat in the spin polaron formulation at finite temperature

    AA Morales, DM Yanga, S Kurihara

    JOURNAL OF SUPERCONDUCTIVITY   17 ( 2 ) 283 - 287  2004年04月

     概要を見る

    Entropy and specific heat are calculated using the spin polaron formulation at finite temperature. Our theoretical approach makes use of the Matsubara Green's function method where the interaction term in the S-matrix is the spin polaron Hamiltonian, which is constructed in a representation where holes are described as spinless fermions (holons) and spins as normal bosons. In the absence of this interaction term, the normal entropy and specific heat are obtained from the free holon thermodynamic potential and are found to resemble the BCS expressions in the low temperature regime. A second cumulant expansion of the thermodynamic potential with the spin polaron interaction yields an expression for the specific heat whose dominant term in the low temperature limit and small quasiparticle energy difference, resembles the superconducting-state electronic specific heat of the BCS theory.

  • スピンポーラロンの形成とそのエントロピー及び比熱

    A. A. Morales, D. M. Yanga, 栗原 進

    Journal of Superconductivity   17 ( 2 ) 283 - 287  2004年04月

  • Quasi-Resonant Tunneling of Phonons

    Ippei Danshita, Susumu Kurihara

    Laser Physics   15   371 - 375  2004年

  • Phase dependence of tunneling of phonon excitations between two Bose-Einstein condensates

    Ippei Danshita, Nobuhiko Yokoshi, Susumu Kurihara

    Journal of Low Temperature Physics   134 ( 1-2 ) 737 - 742  2004年01月

     概要を見る

    We consider the tunneling of phonon excitations across a potential barrier spatially separating two condensates, which have different phases. We analyze the relation between the phase difference of two condensates and the coefficient of tunneling transmission by solving the Bogoliubov-de Gennes equations. As a result, the transmission coefficient T depends strongly on because of the -dependent quasi-bound state. © 2004 Plenum Publishing Corporation.

  • 光学格子上のSpin 1 ボソンの超流動-Mott 絶縁体転移

    土屋俊二, 栗原 進, 木村 敬

    Physical Review A   70   043628  2004年

  • フォノンの準共鳴トンネリング

    段下一平, 栗原 進

    Laser Physics   15   371 - 375  2004年

  • ボース・アインシュタイン凝縮体間のフォノントンネリングの位相差依存性

    段下一平, 余越伸彦, 栗原 進

    Journal of Low Temperature Physics   134 ( 1/2 ) 737 - 742  2004年01月

  • Analytical treatment of interacting Fermi gas in arbitrary dimensional harmonic trap

    Hiroyuki Yoshimoto, Susumu Kurihara

    Journal of Physics A   36   10461 - 10470  2003年10月

    DOI

  • 任意次元の調和型ポテンシャルに捕らえられたフェルミ気体の解析的取り扱い

    吉元広行, 栗原 進

    Journal of Physics A   Vol. 36, page 10461   10461 - 10470  2003年10月

  • Superfluidity in 3He-4He double layer

    Nobuhiko Yokoshi, Susumu Kurihara

    Physical Review B   68   064501  2003年08月

  • 3He-4He二重膜における超流動

    余越伸彦, 栗原 進

    Physical Review B   Vol. 68, page 064501   064501  2003年08月

  • Perturbation theory of spin-1 Bose-Einstein condensates

    S Ohtsuka, S Kurihara

    PHYSICAL REVIEW A   68 ( 1 ) 013601  2003年07月

     概要を見る

    We generalize the perturbation theory of weakly interacting bosons to Bose-Einstein condensates with hyperfine spin F=1. Analytical expressions of second-order self-energies beyond the mean-field approximation are derived at zero temperature. We further extend the perturbation theory to the finite-temperature case, and derive the corresponding self-energies. We evaluate these self-energies near the poles of the first-order (mean-field) Green's functions within the on-shell approximation, and expand the results in powers of wave number in the long-wavelength limit. Excitation spectra for each mode are obtained analytically at low temperatures. We also derive the ground-state energy and thermodynamic quantities such as free energy of the system.

    DOI

  • Singlet superconductivity phase in carbon nanotubes

    Kenji Kamide, Takashi Kimura, Munehiro Nishida, Susumu Kurihara

    Physical Review B   68   024506  2003年07月

  • スピン1をもつボース・アインシュタイン凝縮体の摂動理論

    大塚晋吾, 栗原 進

    Physical Review A   Vol. 68, No.1, 013601-1   013601  2003年07月

  • カーボンナノチューブにおける一重項超伝導相

    上出健仁, 木村 敬, 西田宗弘, 栗原 進

    Physical Review B   68   024506  2003年07月

  • Josephson π states in superfluid 3He B -phase /A-phase /B-phase junctions

    Munehiro Nishida, Susumu Kurihara, Noriyuki Hatakenaka

    Physica B   329   84 - 85  2003年05月

    DOI

  • Superconducting and density-wave correlation functions in carbon nanotubes

    K Kamide, M Nishida, S Kurihara

    PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES   18 ( 1-3 ) 218 - 219  2003年05月

     概要を見る

    We discuss the phase diagrams obtained by calculating temperature dependences of superconducting and density-wave correlation functions for a single (5, 0) carbon nanotube (CN). We use one-loop renormalization group method within logarithmic accuracy. In this system, we must specify scattering channels in terms of momentum along the circumferential direction as well as the axis direction, because (5,0) CN has two degenerate bands crossing the Fermi energy with circumferential momenta. We find that the most divergent order is singlet superconducting or charge-density wave with 0 or 10pih/2piR circumferential momentum, where R is the tube radius. (C) 2002 Elsevier Science B.V. All rights reserved.

    DOI

  • Superconductor-insulator transition in a random two-dimensional system

    Masahiko Kasuga, Susumu Kurihara

    Physica C   384   47 - 53  2003年

    DOI

  • Critical behavior of disordered superconducting-insulating transition in two-dimensional systems

    Masahiko Kasuga, Susumu Kurihara

    Physica C   384   307 - 313  2003年

    DOI

  • 超流動3HeのB相/A相/B相 型接合におけるジョセフソンπ状態

    西田宗弘, 栗原 進, 畠中憲之

    Physica B   Vol. 329-333   84 - 85  2003年

  • カーボンナノチューブにおける超伝導と電荷密度波の相関関数

    上出健仁, 西田宗弘, 栗原 進

    Physica E   18   218 - 219  2003年

    DOI

  • 乱れた2次元系における超伝導・絶縁転移

    春日正彦, 栗原 進

    Physica C   384   47 - 53  2003年

    DOI

  • 2次元系の超伝導・絶遠転移における臨界的振舞い

    春日正彦, 栗原 進

    Physica C   384   307 - 313  2003年

  • Collective Excitations of Dilute Bose-Fermi Superfluid Mixtures

    B. H. Valtan, Munehiro Nishida, Susumu Kurihara

    Laser Physics   12  2002年12月

  • The hole spectral function in the finite temperature Green's function scheme

    AA Morales, DM Yanga, S Kurihara

    JOURNAL OF SUPERCONDUCTIVITY   15 ( 4 ) 277 - 280  2002年08月

     概要を見る

    Using the finite temperature (Matsubara) Green's function method, the hole spectral function is calculated in a representation where holes are described as spinless fermions (holons) and spins as normal bosons. The holon self-energy term for multiple spin-wave processes is analytically determined with the spin polaron Hamiltonian as the interaction term in the S-matrix. The usual prescription of analytic continuation then enables us to obtain the retarded expression from the Matsubara self-energy term yielding the holon spectral function.

  • 有限温度グリーン関数法における正孔スペクトル関数

    A. A. Morales, D. M. Yanga, 栗原 進

    Journal of Superconductivity   15 ( 4 ) 277 - 280  2002年08月

  • Spectral weight, excitation stability and critical velocity in a Bose-condensed gas

    S Ohtsuka, K Sano, S Kurihara

    PROGRESS OF THEORETICAL PHYSICS   107 ( 5 ) 903 - 915  2002年05月

     概要を見る

    We study the excitation spectrum of a spatially homogeneous Bose-condensed gas. Using finite-temperature field theory, we derive the dependence of the excitation spectrum on both the gaseous parameter and the temperature. In particular, we derive the asymptotic forms of the spectral weight at finite temperature. We then discuss the effects of the interaction between the excitations on the dispersion relation, in particular on its curvature for small momentum. From the gaseous parameter dependence of the curvature at zero temperature, we find that there exists a threshold for the gaseous parameter, above which the spectrum becomes stable and no damping processes occur. The excitation stability is analyzed at finite temperature, and it is found that the effect of the finite temperature is to increase the stability of the excitation. We numerically calculated the ratio of the critical velocity to the sound velocity, finding that the critical velocity is small compared to the sound velocity for specific gaseous parametcrs and temperatures.

    DOI

  • Quantum interference of a damped particle

    S Ohtsuka, S Kurihara

    PROGRESS OF THEORETICAL PHYSICS   107 ( 5 ) 889 - 902  2002年05月

     概要を見る

    We study the influence of damping on quantum interference of a particle in free space and in a harmonic potential. Using the influence-functional method, it is shown that the suppression of quantum interference is described by the ratio of the thermal diffusion induced by the environment to the quantum-mechanical diffusion. We describe the interference pattern as a function of the friction constant and the temperature, and discuss the difference between the strong damping limit and the classical limit.

    DOI

  • ボース凝縮気体における素励起のスペクトル強度、安定性、及び臨界速度

    大塚晋吾, 栗原 進

    Progress of Theoretical Physics   107 ( 5 ) 903 - 915  2002年05月

    DOI

  • 減衰のある粒子の量子干渉

    Progress of Theoretical Physics   107/889   889 - 902  2002年05月

    DOI

  • Supercurrent through hybrid junctions with anisotropic Cooper-pair condensates

    M Nishida, N Hatakenaka, S Kurihara

    PHYSICAL REVIEW LETTERS   88 ( 14 ) 145302  2002年04月

     概要を見る

    general formula for the supercurrent between different internal structures in a wide class of hybrid junctions is derived on the basis of the Andreev-reflection picture. The formula extends existing formulas and also enables us to analyze novel B-phase/A-phase/B-phase junctions in super fluid He-3 systems. We propose a mechanism for pi states due to the (l) over cap texture in the A phase of the junction, which could elucidate major features of the pi states with higher critical current (H states) discovered in super fluid 3 He weak links. The bistability of the pi states is also discussed.

    DOI

  • 複合型の接合を通して流れる異方的クーパー対凝縮体間の超電流

    西田宗弘, 畠中憲之, 栗原 進

    Physical Review Letters   88   145302  2002年03月

  • 希薄なボース・フェルミ混合超流体の集団励起

    B. H. Valtan, 西田宗弘, 栗原 進

    Laser Physics   12   217 - 222  2002年

  • Topological excitations in spinor Bose-Einstein condensates

    S Tuchiya, S Kurihara

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   70 ( 5 ) 1182 - 1185  2001年05月

     概要を見る

    We investigate the properties of skyrmion in the ferromagnetic state of spin-1 Bose-Einstein condensates by means of the mean-field theory and show that the size of a skyrmion is fixed to the order of the healing length. It is shown that the interaction between two skyrmions with oppositely rotating spin textures is attractive when their separation is large, following a unique power-law behavior with a power of -7/2.

    DOI

  • Is evolution from weak to strong coupling superconductivity always continuous?

    S Saito, H Yoshimoto, YY Suzuki, S Kurihara

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   70 ( 5 ) 1186 - 1189  2001年05月

     概要を見る

    We have performed a variational analysis on the evolution of superconductivity from weak to strong coupling regime. We have improved the Bardeen Cooper Schrieffer (BCS) wave function, and show that the electronic correlations are important in obtaining the correct behavior of superconducting condensation energy In contrast to a crossover without thermodynamic anomaly discussed in a dilute system. we show the existence of a quantum phase transition near half filling. which suggests that an evolution is not always continuous. The transition is driven by charge density waves instabilities. We have found that superconductivity and charge density waves coexist in the presence of a weak intersite repulsion. The ground state phase diagram is determined by varying both interactions and filling.

    DOI

  • スピン自由度のあるボース・アインシュタイン凝縮体における位相幾何学的な励起

    土屋俊二, 栗原 進

    Journal of the Physical Society of Japan   70   1182 - 1185  2001年05月

  • 弱結合から強結合超伝導への発展は常に連続的か?

    斎藤慎一, 吉元広行, 鈴木康夫, 栗原 進

    Journal of the Physical Society of Japan   70   1186 - 1189  2001年05月

    DOI

  • Infrared divergence in d.c. Josephson current through charge density wave

    K Sano, S Kurihara

    PHYSICA C   351 ( 3 ) 308 - 322  2001年04月

     概要を見る

    We calculate the d.c. Josephson current through charge density wave (CDW) region connected to two superconductors (S-1, S-2) by tunnel junctions. At T = 0 and without impurities, we discover infrared divergence in the d.c. Josephson current caused by the phase mode in the long-junction limit: d/nu (F) >> (h) over bar/Delta (s), (h) over bar/Delta (CDW) where T is temperature. These limits are expressed by using the energy gap in S region Delta (S), the length d, the Fermi velocity nu (F), and the energy gap Delta (CDW) in CDW region. The critical current is proportional to (Delta (CDW)(h) over bar nu (F)/d)(1/2) proportional to Delta (CDW) (xi (CDW)/d)(1/2). At beta Delta (S)(T), beta Delta (CDW)(T) >> 1 and B (h) over bar nu (F)/d << 1, the T-dependence of the correction caused by the phase mode is T-linear where beta = 1/k(B)T and k(B) is Boltzmann constant, At finite temperatures and with impurities, the correction caused by the phase mode becomes proportional to ln T. At finite temperatures and without impurities, the critical current is similar to the Ambegaokar-Baratoff formula which is proportional to Deltas(T) in the short-junction limit: d/nu (F) << (h) over bar/Delta (S), (h) over bar/Delta (CDW). (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI

  • Infrared anomaly of dc Josephson current in super/charge density wave/super Josephson junctions

    K Sano, S Kurihara

    PHYSICA C   352 ( 1-4 ) 223 - 227  2001年04月

     概要を見る

    We calculate de Josephson current through charge density wave (CDW) region connected to two superconductors (S-1, S-2) by tunnel junctions at zero temperature. We discover infrared anomaly of the de Josephson current caused by phase mode in the long junction limit. In this limit, the Josephson current is proportional to the characteristic energy consisting of physical quantities in CDW region, while in the short junction limit, the Josephson current is similar to the Ambrgaokar-Baratoff formula which is proportional to the energy gap of superconductor. (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI

  • Resonant states and currents in superconducting multilayers

    H Ishikawa, S Kurihara, Y Enomoto

    PHYSICA C   350 ( 1-2 ) 62 - 68  2001年02月

     概要を見る

    We calculated electronic states and Josephson currents for superconducting multilayers with one-dimensional SISIS and SNSNS junctions, where S is a superconductor, I, an insulator, and N, a normal metal. We obtained numerical solutions of the Bogoliubov-de Gennes equations for the case where the Fermi wavelength of quasi-electrons and quasiholes is comparable to the coherence length, barrier width, and thickness of the intermediate superconductor. It was found that the maximum Josephson current has a peak structure as a function of barrier height slightly above the Fermi energy, because of resonant tunneling of quasi-electrons and quasi-holes. Though the maximum Josephson current of the SNSNS double junction is smaller than that of the SNS single junction, the maximum Josephson current of the SISIS junction is larger than that of the SIS junction for a range of barrier heights above the Fermi energy. The Josephson current is a superposition of sin(phi /2) and sin phi terms, where rp is a phase difference of the superconductors in both ends. The sin(phi /2) term is dominant for the SISIS junction, while the sin phi, term dominates the SNSNS junction, and their coefficients vary continuously as a function of the barrier height. (C) 2001 Elsevier Science B.V. All rights reserved.

    DOI

  • 超伝導多層膜における共鳴状態と電流

    石川英明, 栗原 進

    Physica C   350   62 - 68  2001年

    DOI

  • 電荷密度波を介したジョセフソン超電流の赤外発散

    佐野一雄, 栗原 進

    Physica C   351   308 - 322  2001年

    DOI

  • 超伝導/電荷密度波/超伝導型ジョセフソン接合におけるジョセフソン超電流の赤外異常

    佐野一雄, 栗原 進

    Physica C   352   223 - 227  2001年

    DOI

  • Josephson phase dynamics in He-3 weak links

    K Matsunaga, M Nishida, D Matsumoto, S Kurihara, N Hatakenaka, H Takayanagi

    PHYSICA B   284   285 - 286  2000年07月

     概要を見る

    We propose a simple phenomenological model for dissipative dynamics of a superfluid. Qualitative agreement between the results of our numerical calculations and of the experiment on a superfluid helium three weak link system gives strong support for our model. (C) 2000 Elsevier Science B.V. All rights reserved.

    DOI

  • Electronic states and currents in superconducting multilayers

    H Ishikawa, S Kurihara, Y Enomoto

    PHYSICA C   336 ( 3-4 ) 181 - 191  2000年07月

     概要を見る

    We obtain full, exact numerical solutions for eigenvalue problems of the Bogoliubov-de Gennes (BdG) equations for the case of superconducting multilayers. Furthermore, the transport current was calculated. This powerful numerical calculation enables us to get solutions for systems with arbitrary barrier and pair potentials where the Fermi-wavelength for quasi-electrons and quasi-holes is comparable to the size of the Cooper pair and coherence length. We apply this new method to one-dimensional SIS and SNS junctions, where S is a superconductor, I is an insulator, and N is a normal metal. It was found that even in this simple system the Josephson current differs from the perfect sinusoidal function and its components through continuous and quasi-bound states have a variety of directions and magnitudes owing to the wave nature of quasi-electrons and quasi-holes. (C) 2000 Elsevier Science B.V. All rights reserved.

    DOI

  • Effect of finite screening length on charge Kosterlitz-Thouless-Berezinskii transition

    Y Miyachi, S Kurihara

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   69 ( 7 ) 2356 - 2357  2000年07月

    DOI

  • Kosterlitz-Thouless-Berezinskii転移における有限遮蔽長の効果

    宮地幸哉, 栗原 進

    Journal of the Physical Society of Japan   69 ( 7 ) 2356 - 2357  2000年07月

    DOI

  • 超流動3He系におけるJosephson位相動力学

    松永慶子, 西田宗弘, 松本大地, 栗原 進, 畠中憲之, 高柳英明

    Physica B   284-288/,285   285 - 286  2000年

  • 無元次元引力ハバード模型に対するGutwiller型射影BCS基底状態

    Progress of Theoretical Physics   102/953  2000年

  • 超伝導多層膜における電子状態と超電流

    Physica C   336   181 - 191  2000年

    DOI

  • Quantum Phase Transition in d=∞ Hubbard Model

    物性研究   72; 6  1999年09月

  • 無限次元ハバードモデルの量子相転移

    斎藤慎一, 鈴木康夫, 栗原 進

    物性研究   71/4,656  1999年

  • d=∞ Hubbardモデルの量子相転移

    斎藤慎一, 鈴木康夫, 栗原 進

    物性研究   72/6,840  1999年

  • 微細なトーラス中に閉じこめられた超流体の減衰:位相すべりの量子核形成

    Journal of the Physical Society of Japan   68/12,  1999年

  • 超固体相への量子相転移

    Journal of Superconductivity   12/,231  1999年

    DOI

  • Quantum Transition to Supersolid Phase

    Journal of Superconductivity/Plenum Publishing Corporation   12(231)  1999年

    DOI

  • Gutzwiller-Type Projected BCS Ground States for Attractive Hubbard Model in Infinite Dimensions

    Progress of Theoretical Physics   102; 5  1999年

    DOI

  • Decay of Superflow Confined in Thin Torus: Quantum Nucleation of Phase Slips

    Journal of the Physical Society of Japan   68; 12  1999年

    DOI

  • 無限次元ハバード・モデルの量子相転移

    物性研究   71; 4  1999年01月

  • 無限次元ハバード模型における量子相転移

    Journal of Low Temperature Physics   113/,897  1998年

  • Quantum Phase Transition in the Infinite Dimensional Hubbard Model

    Journal of Low Temperature Physics/ Plenum   113(897)  1998年

    DOI

  • Coexistence of Superconductivity and Charge Density Waves in d=∞ Attractive Hubbard Model

    Recent Progress in Many-Body Theories/World Scientific   5, p506  1998年

  • 超伝導電流によって制御されたAndreev反射凖粒子波の多重ビ-ム干渉計(理論)

    Japanese Journal of Applied Physics   35/2638  1996年

    DOI

  • ジョセフソンカスケード型マイクロメーザー

    Physical Review A   54/1729  1996年

    DOI

  • ジョセフソン マイクロメーザー

    Czechoslovakian Journal of Physics   46/2311  1996年

  • STM単電子トンネリングに対する表面音響フォノンの効果

    Physica B   219-220/723  1996年

  • STM型接合におけるトンネル距離の固定現像:表面音波の影響

    Physical Review B   53/10402  1996年

    DOI

  • 位相共役共鳴器系を用いたスクィ-ズド光の生成原理

    Physics Letters A   204/,223  1995年

▼全件表示

書籍等出版物

  • 超伝導でたどるメゾスコピックの世界

    栗原 進

    岩波書店  2004年09月

  • Electronic States and Josephson Currents in Superconducting Multilayers

    Hideaki Ishikawa, Susumu Kurihara, Y. Enomoto

    , Studies of High Temperature Superconductors , ed. A. Norikar, Nova Science Publishers, NY.  2001年

  • 超伝導多層膜の電子状態とジョセフソン電流

    石川英明, 栗原 進

    Studies of High Temperature Superconductors, Nova Science Publishers, NY.  2001年

  • 無限次元引力ハバード模型における超伝導と電荷密度波の共存

    Recent Progress in Many-Body Theories, World Scientific  1998年

  • 微小接合・トンネル効果共著(シリーズ物性物理の新展開「メゾスコビック系の物理」第5章)シリーズ全体の編集委員兼任

    メゾスコピック系の物理  1996年

  • メゾスコピック系の物理

    丸善株式会社  1996年

  • トンネル効果編・著(シリーズ物性物理の新展開)シリーズ全体の編集委員も兼任

    丸善  1994年

▼全件表示

共同研究・競争的資金等の研究課題

  • Nelsonの量子力学に基づくトンネリング時間及びその周辺の研究

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(重点領域研究)

  • ヘリウム2重膜における新しいタイプの超流動

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(萌芽的研究)

  • 21世紀COEプログラム 「多元要素からなる自己組織系の物理」

  • COE : 分子ナノ工学