954 citations
- The University of TokyoJP59 papers
- Kyushu UniversityJP13 papers
- University of Electro-CommunicationsJP13 papers
- Centre National de la Recherche ScientifiqueFR12 papers
- Kyoto UniversityJP12 papers
- The University of OsakaJP11 papers
- Max Planck Institute for the Physics of Complex SystemsDE10 papers
- Gakushūin School CorporationJP9 papers
- University of TsukubaJP9 papers
- Tokyo Institute of TechnologyJP8 papers
- Ariel UniversityIL7 papers
- Keio UniversityJP7 papers
6 papers · 1 filter
From Nagaoka's ferromagnetism to flat-band ferromagnetism and beyond: An introduction to ferromagnetism in the Hubbard model
Hal Tasaki
This is a self-contained review about ferromagnetism in the Hubbard model, which should be accessible to readers with various backgrounds who are new to the field. We describe Naga…
Decay of Superconducting and Magnetic Correlations in One- and Two-Dimensional Hubbard Models
Tohru Koma, Hal Tasaki
In a general class of one and two dimensional Hubbard models, we prove upper bounds for the two-point correlation functions at finite temperatures for electrons, for electron pairs…
Symmetry Breaking and Finite Size Effects in Quantum Many-Body Systems
Tohru Koma, Hal Tasaki
We consider a quantum many-body system on a lattice with a continuous symmetry which exhibits a spontaneous symmetry breaking in its infinite volume ground states, but in which the…
Classical XY Model in 1.99 Dimensions
Tohru Koma, Hal Tasaki
We consider the classical XY model (O(2) nonlinear sigma-model) on a class of lattices with the (fractal) dimensions 1<D<2. The Berezinskii's harmonic approximation suggests that t…
From Quantum Dynamics to the Canonical Distribution: General Picture and a Rigorous Example
Hal Tasaki
Derivation of the canonical (or Boltzmann) distribution based only on quantum dynamics is discussed. Consider a closed system which consists of mutually interacting subsystem and h…
Interaction Effects on the Conductance in One-Dimensional Systems -- Short-Range Interaction --
Arisato Kawabata
We investigate the effect of electron-electron interactions on the conductance of quasi one-dimensional systems without potential scattering. For a finite temperature or system len…