Open AccessSpin excitations in the Kitaev-Heisenberg model: Popov-Fedotov fermionization
Author(s) -
Phạm Thu Nga,
Nguyen Van Hinh,
Nguyen Toan Thang
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1932/1/012014
Subject(s) - physics , bravais lattice , spin wave , heisenberg model , quantum mechanics , boson , square lattice , lattice (music) , spin (aerodynamics) , mathematical physics , theoretical physics , ferromagnetism , chemistry , acoustics , crystal structure , ising model , crystallography , thermodynamics
We study a Kitaev-Heisenberg model of spin 1/2 using the Popov-Fedotov fermionization proccedure. We derive the free energy of the quantum spin system on a Bravais lattice within one-loop approximation with exact on-site constraint. We discuss the obtained magnetic excitation spectrum for a particular case of square lattice in relation to the data derived by the equation of motion method and with the result of the linear spin wave theory in Holstein - Primakoff representation.