Eur. Phys. J. Plus (2021) 136: 789
https://doi.org/10.1140/epjp/s13360-021-01779-0

Regular Article

Quantum correlation in the bilinear–biquadratic model for iron-based superconductors

Department of Physics, Federal Center for Technological Education of Minas Gerais, 30510-000, Belo Horizonte, MG, Brazil

^a lslima7@yahoo.com.br, lslima@cefetmg.br

Received: 28 May 2021
Accepted: 20 July 2021
Published online: 31 July 2021

Abstract

Quantum correlation in the spin-1 bilinear–biquadratic model is investigated using the SU(3) flavor-wave formalism. The calculations are performed for the model in the quadrupolar phases. We calculate the von Neumann entropy as a function of the biquadratic couplings $J_{b{q}_{\nu }}$, $\nu =1,2$ and next-nearest-neighboring exchange interactions on square lattice with aim to verify the effect of the different phase transitions, like the transition between nematic phases, on quantum entanglement. Calculations using density matrix renormalization group for the behavior of the concurrence as a function of the biquadratic interaction $J_{b{q}_2}$ are also presented.