A 2D quantum antiferromagnet with a four-fold degenerate valence-bond-solid ground state
@inproceedings{Gelle2007A2Q,
title={A 2D quantum antiferromagnet with a four-fold degenerate valence-bond-solid ground state},
author={Alain Gell'e and Andreas M. Lauchli and Brijesh Kumar and Fr{\'e}d{\'e}ric Mila},
year={2007}
}We study the competition between antiferromagnetic order and valence bond solid formation in a two-dimensional frustrated spin-1/2 model. The J1-J2 model on the square lattice is further frustrated by introducing products of three-spin projectors which stabilize four dimer-product states as degenerate ground states. These four states are reminiscent of the dimerized singlet ground state of the Shastry-Sutherland model. Using exact diagonalizations, we study the evolution of the ground state by…
