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[ 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 ]

## 2007

 19N1120()@1400 @ 薼 ʎqhbgɂ銮Svv @ ut C Tm @ w @ ꏊ pwU@4K[~iP2|432j

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 19N118()@1600 @ 薼 KeldyshɊÂ]XRsbNn̔񕽍tvیƃVbgmCY @ ut B @ w @ ꏊ pwU@4K[~iP2|432j

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 19N126()@1500 @ 薼 Superconductivity in metals without inversion symmetry @ ut Manfred Sigrist @ Theoretische Physik, ETH, Switzerland @@@@@@@@@@@and Depertment of Physics, Kyoto Univ. @ ꏊ pwU@4K[~iP2|432j

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During the last two years the topics of superconductivity in materials without inversion center has experienced renewed interest, initiated through the discovery of the heavy Fermion superconductor CePt3Si, and several other compounds found subsequently. These superconductors show a number of unusual properties, in particular in high magnetic fields The key to understand these features lies very likely in the presence of antisymmetric spin-orbit coupling, whose role for superconductivity and some normal state properties will be discussed in this talk. Moreover the present experimental situation will be reviewed.

## 2006

 PWNWPW()@PTOO @ 薼 Continuous-time strong coupling expansion method for quantum impurity models @ ut Philipp Werner @ Columbia University, USA @ ꏊ pwU@SK[~iPQ|SRQj

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I will present a new continuous-time solver for general classes of quantum impurity models. The method is based on a diagrammatic expansion of the partition function in the impurity-bath hybridization. This expansion leads to a determinantal QMC algorithm, which does not appear to suffer from a sign problem. As a strong- coupling approach, the method becomes particularly powerful at strong interactions and allows access to very low temperatures. I will demonstrate its usefulness via applications to the dynamical mean field theory of the Hubbard and Kondo lattice models.

 PWNUX()@PTOO @ 薼 ʎqhbgɂOkނƋߓ @ ut VH ^ @ ICORPʎqXsvWFNg @ ꏊ pwU@SK[~iPQ|SRQj

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 PWNSPR()@PTOO @ 薼 Strongly correlated electrons and field dependent renormalised parameters - Transport through quantum dots in a magnetic field @ ut Johannes Bauer @ Imperial College, London, UK @ ꏊ pwU@SK[~iPQ|SRQj

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I will describe how quasiparticles in a magnetic field of arbitrary strength H can be described by field dependent parameters. This approach is illustrated in the case of an Anderson impurity model, where the numerical renormalisation group (NRG) is employed to calculate the renormalised parameters. In the Kondo or strong correlation limit of the model the progressive de-renormalisation of the quasiparticles can be followed as the magnetic field is increased. At low temperatures quantum dot systems can be described by an Anderson impurity model, and the differential conductance for the current through the dot can be inferred from the local spectral density. In a renormalised perturbation theory (RPT) the low energy behaviour of the spectral as well as dynamic response functions can be calculated. We present results for such quantities deduced from a RPT and compare with corresponding results from NRG calculations. For a full description of the transport through quantum dots a non-equilibrium description is required. We give results for an asymptotic correct expansion for small, but finite voltage and explain how the behaviour for higher energies and voltages of the order of the Kondo scale can be analysed. A future objective is the quantitative explanation of the magnetic field induced Kondo splitting observed in the differential conductance.

 PWNRPT()@PTOO @ 薼 The emerging new picture of BaVS3: experiments and theory @ ut P. Fazekas @ Reseach Institute for Solid State Physics and Optics, Budapest, Hungary @ ꏊ pwU@SK[~iPQ|SRQj

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The speaker mainly reports on experiments done by his friends at Budapest, Lausannne, and elsewhere. These include ARPES, magnetoresistivity in a wide range of T (sometimes up to 600K), p (up to 2.7GPa), and B (up tp 12T). Widespread hysteresis is found both below and above the critical pressure, but never an explicit first order transition. There is a wide range of NFL behavior, suggesting a critical phase rather than effects by an isolated critical point. We made a preliminary mapping out of the phase diagram of Sr-doped BaVS3. ARPES and IR optics suggest that the basic model of BaVS3 is much more complicated than that of some canonical Mott systems: it is more like a periodic Anderson model based on the coexistence of wide and narrow d-bands, with magic values of fractional filling, enabling the system undergo a spin-orbital Peierls transition to drive its metal-insulator transition. The low-T magnetic phase is still a mystery, and the metal-insulator transition is not much easier. The experimental situation and some naive attempts at theoretical modelling are discussed.

 PWNRR()@PTOO @ 薼 Theory of superconductivity in non-centrosymmetric materials @ ut Manfred Sigrist @ Theoretische Physik, ETH-HAonggerberg, Switzerland @ ꏊ pwU@SK[~iPQ|SRQj

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The recently discovered heavy Fermion superconductor CePt_3Si displays various intriguing properties. The upper critical field exceeds the paramagnetic limit for all field directions. While NMR shows a Hebel-Slichter peak indicating an enhancement due to coherence effects (a feature of conventional Cooper-pairing), several thermodynamic quantities display power-law behavior consistent with line nodes in the quasiparticle gap. The key to the understanding of these features lies in the antisymmetric spin-orbit coupling which is present due to the lack of inversion symmetry in CePt_3Si. This leads to a lifting of the spin degeneracy in a special form which influences Cooper pairing dramatically and makes the classification in even/odd parity or spin singlet/triplet states obsolete. In a model calculation we show that a pairing state belonging to the most symmetric representation of the point group C_{4v} can account for the observed phenomena. This state may be viewed as a superposition of an s-wave and p-wave state which yields a particular gap form with accidental line nodes and, simultaneously, has a finite coherence factor. A further intriguing aspect is the possibility that in the high field regimes a helical superconducting phase may be induced for certain field directions. The presence of such a phase could explain the approximate isotropy of the very large upper critical field. Finally, comments will be given on other non-centrosymmetric superconductors in the light of our discussion.

## 2005

 PVNPQPT()@PUOO @ 薼 Half-magnetization plateau stabilized by structural distortion in the antiferromagnetic Heisenberg model on a pyrochlore lattice @ ut Karlo Penc @ Research Institute for Solid State Physics and Optics, Hungary @ ꏊ pwU@SK[~iPQ|SRQj

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Magnetization plateaus, visible as anomalies in magnetic susceptibility at low temperatures, are one of the hallmarks of frustrated magnetism. We show how an extremely robust half-magnetization plateau can arise from coupling between spin and lattice degrees of freedom in a pyrochlore antiferromagnet, and develop a detailed symmetry analysis of the simplest possible scenario for such a plateau state. The finite temperature phase diagram is determined from Monte Carlo studies. The application of this theory to the spinel oxides CdCr2O4 and HgCr2O4,where a robust half magnetization plateau has been observed, is discussed.

 PVNUPV()@PTOO @ 薼 Energy optimization of  strongly correlated wave functions @ ut S. Sorella @ International School for Advanced Studies (SISSA), Italy @ ꏊ pwU@SK[~iPQ|SRQj

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An appropriate  iterative scheme for the minimization of the energy is  introduced. based on  the variational Monte Carlo (VMC) technique. Indeed, by using   a very efficient statistical evaluation of the first and the second energy derivatives, it is possible to define a very rapidly converging iterative scheme that, within VMC, is much more convenient than the standard and well known Newton method[1]. We present  preliminary results for the optimization of the energy using correlated wave functions containing several parameters. We show that the accurate and unbiased determination of the long range  charge or spin Jastrow factor is particularly important for the determination of the correct low energy physics in one dimensional strongly correlated models, such as the Heisenberg antiferromagnet  or  the one dimensional Hubbard model. In the latter model the same wave function can characterize the Mott insulating phase at one electron per site filling and the Luttinger liquid metal at finite doping. This powerful technique can be particularly important for understanding the role of  strong correlation in higher dimensional systems where no exact solution is available.

 PVNTPW()@PTOO @ 薼 Orbital-selective Mott transitions in the anisotropic two-band Hubbard model at finite temperatures @ ut Carsten Knecht @ Johannes Gutenberg University, Germany @ ꏊ pwU@SK[~iPQ|SRQj

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The anisotropic degenerate two-orbital Hubbard model is studied within dynamical mean-field theory at low temperatures. High-precision calculations on the basis of a refined quantum Monte-Carlo method reveal that two distinct orbital-selective Mott transitions occur for a band-width ratio of 2 even in the absence of spin-flip contributions to the Hund exchange. The second transition - not seen in earlier studies using QMC, iterative perturbation theory, and exact diagonalization - is clearly exposed in a low-frequency analysis of the self-energy and in local spectra.

 PVNSU()@PSOO @ 薼 Dynamical mean-field theory calculation with the dynamical density-matrix renormalization group @ ut { @ University of Goettingen, Germany @ ꏊ pwU@SK[~iPQ|SRQj

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We study the Hubbard model at half band-filling on a Bethe lattice with infinite coordination number at zero temperature. We use the dynamical mean-field theory (DMFT) mapping to a single-impurity Anderson model with a bath whose properties have to be determined self-consistently.@For a controlled and systematic implementation of the self-consistency scheme@we use the fixed-energy (FE) approach to the DMFT. Using the dynamical density-matrix renormalization group method (DDMRG) we calculate the density of states@with a resolution ranging from 3% of the bare bandwidth W=4t at high energies to 0.01% for sharp structures near the Fermi level, e.g., the quasi-particle peak. The DDMRG resolution and accuracy for the density of states is superior to those obtained with other numerical methods in previous DMFT investigations. We find that the critical couplings are U_{c,1}/t=4.45 } 0.05 and@U_{c,2}/t=6.1 } 0.1. We also show existance of two metallic solutions below U=U_{c,1}.

## 2004

 PUNPPQX()@PORO @ 薼 Electrical conductance in molecular system @ ut S. K. Pati @ Jawaharlal Nehru Center for Advanced Scientific Research Bangalore, India @ ꏊ pwU@SK[~iPQ|SRQj

 PUNPOPT()@PRRO @ 薼 pqĈ̗ʎq @ ut R @ NTTȊwb ʎq @ ꏊ pwU@SK[~iPQ|SRQj

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 PUNVQP()@PSOO @ 薼 Excitations in spin liquids: From spin chains to stripes in high-Tc superconductors @ ut G. Uhrig @ Koln University and Tohoku University @ ꏊ pwU@SK[~iPQ|SRQj

 PUNSQP()@PURO @ 薼 Bound states in inhomogeneously doped t-J ladders and t-J bilayers @ ut A. Grzesik @ University of Bonn, Germany @ ꏊ pwU@SK[~iPQ|SRQj

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Doped spin liquids have been subject to significant scientific research for the past two decades, mainly due to their possible relevance to high-temperature superconductors. The existence of a superconducting state depends critically on doping. It was proposed to tune the number of charge carriers non-invasively using field effect devices.
In ladder compounds this can lead to non-uniform doping of the two legs. We model the non-uniformity by a chemical potential difference on the legs of a t-J ladder and investigate its effect on the pairing of holes in the half-filled model. Hole-pairing is a prime indicator for the potential occurence of a superconducting state. We find a strong suppression of the most prominent bound state upon increasing the chemical potential difference, while other features of the spectrum are enhanced.
We also investigate the effect of inhomogeneous doping on bound states in the t-J bilayer model, about the electronic properties of which not much is known. In particular, we find the symmetry of the lowest lying bound state to cross from s-wave to d-wave with increasing inhomogeneity.

 PUNPRO()@PTOO @ 薼 wIȗ̂ddqnɂtF~ť @ ut c gv @ ww@wȉFnȊwU @ ꏊ pwU@SK[~iPQ|SRQj

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 PUNPQU()@PTOO @ 薼 metal-insulator transitions in some 4d transition metal oxides with the pyrochlore structure @ ut T. W. Noh @ School of Physics and Research Center for Oxide Electoronics, Seoul National University @ ꏊ pwU@SK[~iPQ|SRQj

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Recently, there have been lots of investigation on the 4d transition metal oxides with pyrochlore structures, which shows numerous intriguing phenomena, including geometric frustration, anomalous Hall effects, and metal-insulator transitions (MITs). Using optical spectroscopy techniques, we investigated optical properties of some 4d transition metal oxides, including R_2Mo_2O_7 (R=rare earth metals) and (Bi,Y)_2Ru_2O_7, which have interesting MITs. Inspite of the extended nature of the 4d orbitals, we found that the electron-electron correlation could play important roles in the MITs. By comparing the optical responses with numerous Hubbard models, we will also discuss on the importances of orbital degeneracy and geometric frustration in the MITs observed in these pyrochlore compounds.

## 2003

 PTNPQPT()@PTOO @ 薼 Quantum orbital physics in titanates @ ut Giniyat Khaliullin @ Max-Planck-Institut FKF, Stuttgart @ ꏊ pwU@SK[~iPQ|SRQj

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We discuss a collective behavior of orbital angular momentum in Mott insulators with t_2g orbital degeneracy. The frustrated nature of the superexchange interactions leads to an infinite degeneracy of classical states. Quantum effects select a particular orbital state depending on spin configuration: (i) In spin one-half antiferromagnetic LaTiO_3, orbitals remain quantum disordered down to low temperature; (ii) In ferromagnetic YTiO_3, a weak orbital order is stabilized by order-from-disorder mechanism. The Hund's coupling as well as weak lattice distortions, in particular tilting of octahedra, drive a quantum transition between AF and ferromagnetic states in titanates.

(i) G. Khaliullin and S. Maekawa, Phys. Rev. Lett. 85, 3950 (2000).
(ii) G. Khaliullin and S. Okamoto, Phys. Rev. Lett. 89, 167201 (2002); Phys. Rev. B 68, 205109 (2003).

 PTNPPPW()@PRRO @ 薼 [UXNbe_Cg̓dq\ƕ @ ut d @ wYƉȊw @ ꏊ pwU@SK[~iPQ|SRQj

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 PTNPPPP()@PROO @ 薼 Interplay of orbital and spin ordering on the triangular lattice @ ut P. Fazekas @ Reseach Institute for Solid State Physics and Optics, Budapest, Hungary @ ꏊ pwU@SK[~iPQ|SRQj

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@ We study the interplay of spin and orbital degrees of freedom within the trigonal orbital doublet E on the triangle lattice. Both geometry and structural frustration make our model behave differently from the extensively studied cubic E doublets. Trigonal E doublets are found either for 3d^1 as in BaVS_3, or for low-spin 3d^7 as in LiNiO_2 or NaNiO_2.
@ For special parameters, the nearest-neighbor Kugel-Khomskii (nnKK) model is SU(4)-symmetrical. A class of SU(4) model is obtained by changing the interaction range. Combining exact diagonalization, variational approach, and spin wave theory, we find a novel quantum liquid state with SU(4) siglet resonance for the nnKK model, while nnn interaction drives towards four-sublattice long range order [1].
@ The phase diagram of the general trigonal nnKK model is mapped by a combination of numerical, and variational methods [2]. Hopping amplitudes and intra-atomic exchange are control parameters. Besides the SU(4) state, there is a great variety of anisotropic T=0 phases. Spin arrangements include ferromagnetism, dimer coverings, antiferromagnetic chain, and two-dimensional superlattices. Spin ferromagnetism allows several phases with differing orbital character, including complex orbital order.

[1] K. Penc, M. Mambrini, P. fazekas and F. Mila: Phys. Rev. B 68, 012408 (2003).
[2] F. Vernay, K. Penc, P. fazekas and F. Mila: in preparation.

 PTNTPQ()@PROO @ 薼 Exact solution of the Falicov-Kimball model @ ut V. Zlatic @ Institute of Physics, Zagreb, Croatia @ ꏊ pwU@SK[~iPQ|SRQj

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The properties of a number of Yb- and Eu-based intermetallics which exhibit a valence-change transition, like YbInCu4, EuNi2(Si1-xGex)2 or Eu2(Pd1-xPtx)2Si2 are most unusual[1,2,3]. At high temperatures, the magnetization indicates that the rare earth (RE) ions are in a stable configuration, with a local moments close to the free ion value, while transport properties correspond to a bad metal with suppressed Drude weight and temperature independent resistance and magneto-resistance. Surprisingly, the usual Kondo anomalies are not found. At temperature TV the valency of the RE ions changes, the local moments disappear and the band states reconstruct to give a good metal. In the low-temperature phase the susceptibility is Pauli like, the Drude peak is fully developed and the Hall data show a huge increase in the number of carriers. The entropy reduction across the transition is consistent with a complete loss of f-moments, which seem to be quenched by valence uctuations present in the ground state. For T ≤ TV , the high-entropy (magnetic and semi-metallic) phase can be restored by a large enough magnetic field, H ≥ Hc. The values of Hc and TV are pressure- and doping-dependent but the the ratio g=kBTV /BHc seems to be determined by the degeneracy of the magnetic f-states only.
We explain these properties by the dynamical mean field theory (DMFT) of the Falicov-Kimball model[4], which considers the effects of the Coulomb repulsion between the 4f- and conduction-states but also takes into account the degeneracies and the splittings of the 4f-states, and allows the statistical mixing of various f-configurations. The model neglects the quantum uctuations of the f-electron number, which allows the Hilbert space to be reduced and an exact solution to be found[5]. At high temperatures or fields, we find a gap or pseudo-gap in the excitation spectrum of conduction electrons has and a sizable occupation of magnetic f-states. The chemical potential is close to the pseudo-gap, the electrical resistance is large and exhibits a weak maximum at temperatures of the order of the (pseudo) gap, T ≅ T*. The thermoelectric power is also large and with a minimum at T*. The optical conductivity shows a pronounced high-energy peak and suppressed Drude peak. The spin susceptibility of the localized f-states is Curie-like, with the Curie constant given by the number of magnetic ions. The reduction of temperature changes the f-occupancy, and leads at T ≅ TV T* to a rapid crossover to a highly conducting state. The chemical potential is shifted in the region of the high-density of states and the Drude peak dominates the electrical transport. However, since the f-d hybridization is neglected, the ground state is a simple Fermi liquid, rather than a valence uctuator, as observed experimentally. At large enough magnetic field the f-moments are restored and the chemical potential is brought back in the gap or pseudo-gap region.
By tuning the model parameters we obtain the correlation functions of the high-entropy phase, the values of TV and T*, the phase boundary, and the ratio kBTV /BHc, which are quite close to the experimental results. We are particularly concerned with systems such as Yb1-xYxInCu4, in which the high-entropy phase is stabilized by doping or pressure down to very low temperatures. Despite its simplicity, the model accounts in a qualitative way for the temperature, field, doping and pressure dependence of the experimental data.

[1] J.L. Sarrao, Physica B, 259&261, 129 (1999).
[2] H. Wada et al., J. Phys.: Condens. Mat. 9, 7913 (1997).
[3] H. Wada et al., Solid State Commun. 117, 703 (2001).
[4] V. Zlatic et al., Phil. Mag.81, 1443 (2001); J. K. Freericks and V. Zlatic, Phys. Rev. B64, 245118 (2001); J. K. Freericks and V. Zlatic, Rev. Mod. Phys. 75, (2003).
[5] U. Brandt and C. Mielsch, Z. Phys. B, 75, 365, (1989).

 PTNRPV()@PROO @ 薼 The Physics of SU(4) Heisenberg Models @ ut K. Penc @ Research Institute for Solid State Physics and Optics, Hungary @ ꏊ pwU@SK[~iPQ|SRQj

## 2002

 PSNPQX()@PTOO @ 薼 Spin-chirality duality and scalar chiral order in spin ladders with four-spin exchanges @ ut @ }gww@w @ ꏊ pwU@SK[~iPQ|SRQj

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 PSNPPPW()@PTOO @ 薼 1/r2^ݍp1Ώ$t$-$J$͌^̃Xs͊w @ ut L@WO @ {w @ ꏊ pwU@SK[~iPQ|SRQj

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1dqn͑傫ȗʎqh炬̂߁ANGlM[Ɍł iLuttinger̂ƌĂ΂tF~̂ŋLqB ̓̈͓dq̂XsRxƓd׎RxA ꂼXsmAzƌĂ΂fNƂĐUƂłB Apx^dqeqU ɂϑ铮͊wڂ邽߂ɂ LNGlM[̈ɂ铮͊w̑fNKvƂB 1ʎqn͓ʂȏ̂ƂŃx[e@ɂ錵݂邪A SGlM[̈ɂ鑊֊֐̓o͈ʂɍłB $1/r2$^ݍpPΏ$t$-$J$͌^[1]ɂ XsmAz͔M͊w番vɏ]RqƂ݂Ȃ邱ƂmĂ [2]B ɁA̖͌^ɑ΂Ha, Haldane[3]͗lXȑ֊֐̉^-GlM[ ʂł̗L̃XyNgẍ𓱏oB ނ͔M͊wɌɂĊ^NԂL̃XsmCzCAz fN\邱ƂĂB ȂXyNgx ͓̂ĂȂB X͂PdqtXyNg֐[4]ƓlA SU(1,1) Sutherland͌^Ɏʑ邱ƂɂA IXs\q$S(q,\omega)$̉^-GlM[ ʂ̑S̈ɂ킽͌𓾂B {uł́Aꂽ$S(q,\omega)$̉͌Xs͊wɂfN c_B

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[1] Y. Kuramoto and H. Yokoyama, Phys. Rev. Lett. 67, 1338 (1991).

[2] Y. Kuramoto and Y. Kato, J. Phys. Soc. Jpn. 64, 4518 (1995).

[3] Z. N .C. Ha and F. D. N. Haldane, Phys. Rev. Lett. 73, 2887(1994).

[4]M. Arikawa, Y. Saiga and Y. Kuramoto, Phys. Rev. Lett. 86, 3096 (2001).

 PSNPPPT()@PROO @ 薼 Competing Orders in Cuprates @ ut C. Nayak @ UCLA @ ꏊ pwU@SK[~iPQ|SRQj

 PSNPPPP()@PORO @ 薼 What I've Learned About Exactly Solved Models @ ut B. Sutherland @ University of Utah & YITP @ ꏊ pwU@SK[~iPQ|SRQj

AuXgNg

I will give a brief survey of exactly solved models for interacting quantum many-body systems. My choice of topics will be very selective and personal - consisting of both results and questions that interest me. I will discuss: Integrability, non-diffractive scattering and the asymptotic Bethe-ansatz; Strategies for proving integrability; What are the asymptotic momenta?; Tricks-of-the-trade or new models from old.

 PSNPOQR()@PURO @ 薼 _̒̎cɂdq @ ut yY@GI @ CRESTAÉww@HwȉpwU @ ꏊ pwU@SK[~iPQ|SRQj

AuXgNg

̒̎cɂ͏q̑Ԃ݂D ̃GlM[ʓɂ͒Ԃ̑Ώ̐fD Ƃ낪C_̒̎cɂẮCdgΏ̐ ҂鑩Ԃ݂ȂƂŋ߂STS 薾炩ɂȂD ́CcdgȊO̒܂͗h炬 BĂ\ĂD {uł́Cct߂ł̗lXȒ̋ڍׂɌC cŐĂ镨I@\ɂċc_D

 PSNXQ()@PRRO @ 薼 "Signs of a new universality in heavy Fermion quantum critical points " @ ut Catherine Pepin @ SPhT, CEA-Saclay, France @ ꏊ pwU@SK[~iPQ|SRQj

 PSNWQU()@PRRO @ 薼 "Sr2RuO4ɂ " @ ut M. Sigrist @ ETHiXCXAMHȑwj @ ꏊ pwU@SK[~iPQ|SRQj

 PSNWQS(y)@PRRO @ 薼 "Spin-orbital chains in cubic perovskite YVO_3 " @ ut G. Khaliullin @ Max-Planck-Institut FKF Stuttgart, and IMR Sendai @ ꏊ pwU@SK[~ioQ|SRQj
 AuXgNg The one-dimensional spin-orbital model relevant to cubic vanadates will be discussed. Depending on the value of the Hunds coupling the model shows two distinct phases, a 4-site periodic quantum dimer phase, and an uniform ferromagnetic state. Strong dimer correlations develop at finite temperature also on the ferromagnetic side of the transition, as dimer states modulate spin and orbital bonds and release high entropy. This dynamical dimerization might be a mechanism driving intermediate phase of YVO_3.

 PSNSPUiyj PURO @ 薼 "Transfermatrix-DMRG for thermodynamics of extended Hubbard models and dynamics of stochastic models" @ ut Andreas Kemper @ Pw @ ꏊ pwU@SK[~iPQ|SRQj

 PSNRXiyj PTOO @ 薼 "񕽍tߓʂFermi̘_" @ ut I@͎ @ sww @ ꏊ pwU@SK[~iPQ|SRQj

## 2001

 PRNPPXiyj PURO @ 薼 "Dynamical Conservation Laws, Violation of Non Crossing Rule Collapse of Mott Gap in 1-d Hubbard Model" @ ut B. Sriram Shastry @ Indian Institute of Science @ ꏊ pwU@SK[~iPQ|SRQj

 PRNPOQUij PURO @ 薼 "ʎqz[n̓͊wƑfN" @ ut ؁@ @ kww@w @ ꏊ pwU@SK[~iPQ|SRQj

 PRNTV()@PUOO @ 薼 "Magnetic Oscillations in Lower Dimensional Interacting Systems" @ ut Stephanie H. Curnoe @ w @ ꏊ pwU@SK[~iPQ|SRQj

 PRNRPR()@PWRO @ 薼 "MgB2ɂ" @ ut d@ @ wYƉȊw @ ꏊ pwU@SK[~iPQ|SRQj

 PRNQQS(y)@PSOO @ 薼 "Charge and Spin Separation in the 1D Hubbard Model" @ ut V. E. Korepin @ State University of New York, Stony Brook @ ꏊ pwU@SK[~iPQ|SRQj

 PRNQPR()@PRRO @ 薼 "Chiral liquid in the multichannel Kondo-Heisenberg Lattice" @ ut E. Orignac @ Laboratoire de Physique Théorique, Ecole Normale Supérieure @ ꏊ pwU@SK[~iPQ|SRQj

## 2000

 PQNXT()@PRRO @ 薼 "New exact results on quantum spin chains" @ ut J. Zittartz @ Pw @ ꏊ pwU@SK[~iPQ|SRQj

 PQNXS()@PTOO @ 薼 "SrCu2(BO3)2 - a Two-Dimensional Spin Liquid" @ ut G. Uhrig @ Pw @ ꏊ pwU@SK[~iPQ|SRQj

 PQNTQX()@PTOO @ 薼 "Orbital degeneracy and bond fluctuations in manganites" @ ut Giniyat Khaliullin @ kwޗ @ ꏊ pwU@SK[~iPQ|SRQj

 PQNRRO()@PRRO @ 薼 "iPjtXg[ĝɂُz[ @iQjL@̂ɂSO(5)dՊE" @ ut i@l @ ww@HwȕHwU @ ꏊ pwU@SK[~iPQ|SRQj

 PQNRPS()@PPOO @ 薼 "Matrix-product Ansatz for stochastic systems and boundarty-induced phase transitions" @ ut A. Schadschneider @ Institut fur Theoretische Physik, University of Koln @ ꏊ pwU@SK[~iPQ|SRQj

 PQNRU()@PTOO @ 薼 "Low Temperature Properties of a Doped Heisenberg Magnet" @ ut H. Frahm @ Institut fur Theoretische Physik, University of Hannover @ ꏊ pwU@SK[~iPQ|SRQj

 PQNRR()@PTOO @ 薼 "Pressure dependence and non-universal effects of microscopic couplings on the spin-Peierls transition in CuGeO3" @ ut A. Klumper @ Institut fur Theoretische Physik, University of Dortmund @ ꏊ pwU@SK[~iPQ|SRQj

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