Spin-wave approach to the two-magnon Raman scattering in a J1x-J1y-J2-Jc antiferromagnetic Heisenberg model

Abstract

© 2017 American Physical Society. We study the two-magnon nonresonant Raman scattering in the (π,π) and (π,0) in-plane ordered antiferromagnetic phases of a spin-SJ1x-J1y-J2-Jc Heisenberg model on the tetragonal lattice within the framework of the spin-wave theory. We show that magnon-magnon interactions may significantly change the shape of spectra even in large-S cases. We discuss the effects of various tuning factors to the two-magnon Raman spectra. We find that both the magnetic frustration J2/J1 and the interlayer exchange coupling Jc may significantly affect the spectra in both the B1g and the A1g′ channels in the (π,π) Néel ordered phase. Moreover, we find a splitting of the two-magnon peak in the (π,0) collinear antiferromagnetic phase. We further discuss the implications of our results to the BaMnBi2 and iron pnictide systems.