Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2004-10-23
Physics
Condensed Matter
Strongly Correlated Electrons
Revtex, 10 pages, 6 figures, 3 tables
Scientific paper
10.1103/PhysRevB.71.174434
Two quantum spin models with bilinear-biquadratic exchange interactions are constructed on the checkerboard lattice. It is proved that, under certain sufficient conditions on the exchange parameters, their ground states consist of two degenerate Shastry-Sutherland singlet configurations. The constructions are studied for arbitrary spin-S. The sufficient conditions for the existence of ferromagnetic ground state are also found exactly. The approximate quantum phase diagrams are presented using the exact results, together with a variational estimate for the N\'eel antiferromagnetic phase. A two-leg spin-1/2 ladder model, based on one of the above constructions, is considered which admits exact solution for a large number of eigenstates. The ladder model is shown to have exact level-crossing between the rung-singlet state and the AKLT state in the singlet ground state. Also introduced is the notion of perpendicularity for quantum spin vectors, which appears in the discussion on one of the two checkerboard models, and is discussed in the Appendix.
No associations
LandOfFree
Two quantum spin models on the checkerboard lattice with an exact two-fold degenerate Shastry-Sutherland ground state does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Two quantum spin models on the checkerboard lattice with an exact two-fold degenerate Shastry-Sutherland ground state, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Two quantum spin models on the checkerboard lattice with an exact two-fold degenerate Shastry-Sutherland ground state will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-485202