Regular Article - Quantum Information
Quantum correlation and entanglement in the Heisenberg model with biquadratic interaction on square lattice
Department of Physics, Federal Education Center Technological of Minas Gerais, 30510-000, Belo Horizonte, MG, Brazil
Accepted: 23 December 2020
Published online: 21 January 2021
We study the bipartite entanglement as well as the correlation content between two partitions of the quantum 2D Heisenberg model with biquadratic interactions, where the parameter controls the ratio of the biquadratic and exchange couplings. We also investigate the pairwise entanglement between nearest-neighbor qubits. The calculations were performed for the model on square lattice, in the Néel phase and ferroquadrupolar phase using spin wave theory and Schwinger boson approaches. In the Néel phase that corresponds to range , we use the Dyson–Maleev representation and SU(2) Schwinger boson representation to calculate the von Neumann entropy as function of the biquadratic coupling . In the ferroquadrupolar phase, we use the SU(3) Schwinger boson representation which is adequate to treat this phase.
© The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature 2021