4 citations · 4 across the 1 of their papers we have counts for
8 papers
Non linear sigma models and quantum spin systems
A. S. Gliozzi, A. Parola
Microscopic models of quantum antiferromagnets are investigated on the basis of a mapping onto effective low energy hamiltonians. Lattice effects are carefully taken into account a…
Spin liquid ground state in a two dimensional non-frustrated spin model
G. Santoro, S. Sorella, L. Guidoni +2
We consider an exchange model describing two isotropic spin-1/2 Heisenberg antiferromagnets coupled by a quartic term on the square lattice. The model is relevant for systems with…
Spin gap in low-dimensional Mott insulators with orbital degeneracy
L. Guidoni, G. Santoro, S. Sorella +2
We consider the exchange Hamiltonian H_ST = -J Sum_{<rr'>} (2 S_r S_r' - 1/2) (2 T_r T_r' - 1/2) describing two isotropic spin-1/2 Heisenberg antiferromagnets coupled by a quartic…
Anomalous finite size spectrum in the S=1/2 two dimensional Heisenberg model
C. Lavalle, S. Sorella, A. Parola
We study the low energy spectrum of the nearest neighbor Heisenberg model on a square lattice as a function of the total spin S. By quantum Monte Carlo simulation we compute this s…
Theory of hole propagation in one dimensional insulators and superconductors
S. Sorella, A. Parola
The dynamical properties of hole motion in an antiferromagnetic background are determined in one dimensional models in zero magnetic field, where spin isotropy holds, as well as in…
Phase Diagram of a Model of Correlated Hopping of Electrons in a Lattice of Berry Molecules
Giuseppe Santoro, Nicola Manini, Alberto Parola +1
The phase diagram of a model for correlated hopping of electrons in a lattice of Berry phase molecules is presented. Electrons hop in presence of an extra orbital degree of fr…