English

Spin Waves in Random Spin Chains

Disordered Systems and Neural Networks 2009-11-07 v1

Abstract

We study quantum spin-1/2 Heisenberg ferromagnetic chains with dilute, random antiferromagnetic impurity bonds with modified spin-wave theory. By describing thermal excitations in the language of spin waves, we successfully observe a low-temperature Curie susceptibility due to formation of large spin clusters first predicted by the real-space renormalization-group approach, as well as a crossover to a pure ferromagnetic spin chain behavior at intermediate and high temperatures. We compare our results of the modified spin-wave theory to quantum Monte Carlo simulations.

Keywords

Cite

@article{arxiv.cond-mat/0208607,
  title  = {Spin Waves in Random Spin Chains},
  author = {Xin Wan and Kun Yang and Chenggang Zhou and R. N. Bhatt},
  journal= {arXiv preprint arXiv:cond-mat/0208607},
  year   = {2009}
}

Comments

3 pages, 3 eps figures, submitted to the 47th Conference on Magnetism and Magnetic Materials