English

Yangian symmetry in molecule {V6} and four-spin Heisenberg model

Quantum Physics 2010-10-19 v2

Abstract

The symmetry operator Q=Y2Q=Y^2 is introduced to re-describe the Heisenberg spin triangles in the \{V6\} molecule, where Y\mathbf{Y} stands for the Yangian operator which can be viewed as special form of Dzyaloshiky-Moriya (DM) interaction for spin 1/2 systems. Suppose a parallelogram Heisenberg model that is comprised of four 1/2-spins commutes with QQ, which means that it possesses Yangian symmetry, we show that the ground state of the Hamiltonian H4H_4 for the model allows to take the total spin S=1 by choosing some suitable exchange constants in H4H_4. In analogy to the molecular \{V6\} where the two triangles interact through Yangian operator we then give the magnetization for the theoretical molecule "\{V8\}" model which is comprised of two parallelograms. Following the example of molecule \{V15\}, we give another theoretical molecule model regarding the four 1/2-spins system with total spin S=1 and predict the local moments to be 1/10u_B, 9/10u_B, 1/10u_B,9/10u_B respectively.

Keywords

Cite

@article{arxiv.0907.4610,
  title  = {Yangian symmetry in molecule {V6} and four-spin Heisenberg model},
  author = {Xu-Biao Peng and Cheng-Ming Bai and Mo-Lin Ge},
  journal= {arXiv preprint arXiv:0907.4610},
  year   = {2010}
}

Comments

24 pages,8 figures, submitted to Annals of Physics