English

Vector chiral states in low-dimensional quantum spin systems

Strongly Correlated Electrons 2015-05-13 v2

Abstract

A class of exact spin ground states with nonzero averages of vector spin chirality, <Sˇi×Sˇjz^><\v{S}_i \times \v{S}_j \cdot \hat{z}>, is presented. It is obtained by applying non-uniform O(2) rotations of spin operators in the XY plane on the SU(2)-invariant Affleck-Kennedy-Lieb-Tasaki (AKLT) states and their parent Hamiltonians. Excitation energies of the new ground states are studied with the use of single-mode approximation in one dimension for S=1. The excitation gap remains robust. Construction of chiral AKLT states is shown to be possible in higher dimensions. We also present a general idea to produce vector chirality-condensed ground states as non-uniform O(2) rotations of the non-chiral parent states. Dzyaloshinskii-Moriya interaction is shown to imply non-zero spin chirality.

Keywords

Cite

@article{arxiv.0705.3993,
  title  = {Vector chiral states in low-dimensional quantum spin systems},
  author = {Raoul Dillenschneider and Jung Hoon Kim and Jung Hoon Han},
  journal= {arXiv preprint arXiv:0705.3993},
  year   = {2015}
}
R2 v1 2026-06-21T08:32:31.759Z