Faculté des sciences

Phase diagram of the Heisenberg spin ladder with ring exchange

Gritsev, Vladimir ; Normand, Bruce ; Baeriswyl, Dionys

In: Physical Review B, 2004, vol. 69, p. 094431-94446

We investigate the phase diagram of a generalized spin-1/2 quantum antiferromagnet on a ladder with rung, leg, diagonal, and ring-exchange interactions. We consider the exactly soluble models associated with the problem, obtain the exact ground states which exist for certain parameter regimes, and apply a variety of perturbative techniques in the regime of strong ring-exchange coupling. By... Plus

Ajouter à la liste personnelle
    Summary
    We investigate the phase diagram of a generalized spin-1/2 quantum antiferromagnet on a ladder with rung, leg, diagonal, and ring-exchange interactions. We consider the exactly soluble models associated with the problem, obtain the exact ground states which exist for certain parameter regimes, and apply a variety of perturbative techniques in the regime of strong ring-exchange coupling. By combining these approaches with considerations related to the discrete Z4 symmetry of the model, we present the complete phase diagram.