English

Quantum Phase Transitions in Alternating-Bond Mixed Diamond Chains with Spins 1 and 1/2

Strongly Correlated Electrons 2010-03-29 v2 Statistical Mechanics

Abstract

We investigate the mixed diamond chain composed of spins 1 and 1/2 when the exchange interaction is alternatingly distorted. Depending on the strengths of frustration and distortion, this system has various ground states. Each ground state consists of an array of spin clusters separated by singlet dimers by virtue of an infinite number of local conservation laws. We determine the ground state phase diagram by numerically analyzing each spin cluster. In particular for strong distortion, we find an infinite series of quantum phase transitions by the cluster expansion method and conformal field theory. This leads to the infinite series of steps in the behavior of the Curie constant and residual entropy.

Keywords

Cite

@article{arxiv.0911.3838,
  title  = {Quantum Phase Transitions in Alternating-Bond Mixed Diamond Chains with Spins 1 and 1/2},
  author = {Kazuo Hida and Ken'ichi Takano and Hidenori Suzuki},
  journal= {arXiv preprint arXiv:0911.3838},
  year   = {2010}
}

Comments

7 pages, 9 figures