English

Interplay of Quantum Criticality and Geometric Frustration in Columbite

Strongly Correlated Electrons 2010-09-07 v1 Materials Science

Abstract

Motivated by CoNb2O6 (belonging to the columbite family of minerals), we theoretically study the physics of quantum ferromagnetic Ising chains coupled anti-ferromagnetically on a triangular lattice in the plane perpendicular to the chain direction. We combine exact solutions of the chain physics with perturbative approximations for the transverse couplings. When the triangular lattice has an isosceles distortion (which occurs in the real material), the T=0 phase diagram is rich with five different states of matter: ferrimagnetic, N\'eel, anti-ferromagnetic, paramagnetic and incommensurate phases, separated by quantum phase transitions. Implications of our results to experiments on CoNb2O6 are discussed.

Keywords

Cite

@article{arxiv.0911.0038,
  title  = {Interplay of Quantum Criticality and Geometric Frustration in Columbite},
  author = {SungBin Lee and Ribhu K. Kaul and Leon Balents},
  journal= {arXiv preprint arXiv:0911.0038},
  year   = {2010}
}