Numerical study of a t-J ladder model

Oron Zachar

We introduce a new model and mechanism of high temperature pairing in stripes. We propose a way to unambiguously test it by numerical simulations. For example, the implementation of our mechanism in a 6-leg t-J ladder model has the effect of making the spin gap of the doped 6-leg ladder be about 4 times bigger than the spin gap of the same ladder at half filling.

Didier Poilblanc

Daniel Duffy, Stephan Haas, Eugene Kim

The Hubbard Hamiltonian on a two-leg ladder is studied numerically using quantum Monte Carlo and Exact Diagonalization techniques. A rung interaction, $V$, is turned on such that the resulting model has an exact SO(5) symmetry when $V=-U$. The evolution of the low energy excitation spectrum is presented from the pure Hubbard ladder to the SO(5) ladder. It is shown that the low energy excitations in the pure Hubbard ladder have an approximate SO(5) symmetry.

Ken'ichi Takano, Kazuhiro Sano, Ippei Doi

J. C. Amadon, Steven R. White

Daniel Duffy, Stephan Haas, Eugene Kim

The Hubbard Hamiltonian on a two-leg ladder is studied numerically using quantum Monte Carlo and exact diagonalization techniques. A rung interaction, $V,$ is turned on such that the resulting model has an exact SO(5) symmetry when $V=\ensuremath{-}U.$ The evolution of the low-energy excitation spectrum is presented from the pure Hubbard ladder to the SO(5) ladder. It is shown that the low-energy excitations in the pure Hubbard ladder have an approximate SO(5) symmetry.