English

Majorana Fermion Representation For An Antiferromagnetic Spin-1/2 Chain

Condensed Matter 2016-08-31 v2

Abstract

We study the 1-dimensional Heisenberg antiferromagnet with s=1/2 using a Majorana representation of the s=1/2 spins. A simple Hartree-Fock approximation of the resulting model gives a bilinear fermionic description of the model. This description is rotationally invariant and gives power-law correlations in the ``ground state'' in a natural fashion. The excitations are a two-parameter family of particles, which are spin-1 objects. These are contrasted to the ``spinon'' spectrum, and the technical aspects of the representation are discussed, including the problem of redundant states.

Keywords

Cite

@article{arxiv.cond-mat/9603179,
  title  = {Majorana Fermion Representation For An Antiferromagnetic Spin-1/2 Chain},
  author = {B. Sriram Shastry and Diptiman Sen},
  journal= {arXiv preprint arXiv:cond-mat/9603179},
  year   = {2016}
}

Comments

24 pages in LaTeX, no figures; some clarifications/additions have been made following the referee's comments; to appear in Phys. Rev. B