Magnon-phonon coupling effects on the indirect K-edge resonant inelastic X-ray scattering spectrum of a 2D Heisenberg antiferromagnet

Abstract

We compute the effects of magnon-phonon coupling on the indirect K-edge bimagnon resonant inelastic x-ray scattering (RIXS) intensity spectrum of a square lattice Heisenberg antiferromagnet. We analyze the effects of competing nearest and next--nearest magnetic and magnon-phonon coupling interaction in the RIXS spectrum, for both the antiferromagnetic (AF) and the collinear antiferromagnetic (CAF) phases of the model. Utilizing the Dyson-Maleev representation of spin operators, the Bethe-Salpeter ladder approximation scheme for the bimagnon interacting channel, and considering the lowest order magnon-phonon-magnon scattering interaction we highlight distinct features in the X-ray spectrum. Considering damping effects, arising due to the presence of phonons, we find that in the AF phase the RIXS intensity spectrum attains a maximum value primarily localized around the K $\left(\pm \frac{\pi }{2},\pm \frac{\pi }{2}\right)$ - point. For the CAF phase the intensity is broadly distributed with a significant scattering intensity located around the Y $\left(\pm \frac{\pi }{2},0\right)$ - point. Furthermore, in the CAF phase for suitable anisotropy, nearest-, and next-nearest neighbor interaction parameters the phonon effects can manifest itself as a distinct peak both below and above the bimagnon peak. Such a feature is in contrast to the antiferromagnetic spectrum where the effect due to the phonon peak was located consistently beyond the bimagnon peak in the high energy end of the spectrum. Additionally, in the CAF phase we find the RIXS bimagnon-phonon spectrum to be more sensitive to anisotropy compared to its antiferromagnetic counterpart. We conclude that the ultimate effect of magnon-phonon effects in the indirect K-edge RIXS spectrum, in both the antiferromagnetic and the collinear antiferromagnetic phase, is an observable effect.

13 pages, 10 figures, published version

References in corpus (16)

• Inelastic Light Scattering From Correlated Electrons
• Spin-Orbital Separation in the quasi 1D Mott-insulator Sr2CuO3
• A Systematic Study of Electron-Phonon Coupling to Oxygen Modes Across the Cuprates
• Spin excitations in a single La${}_2$CuO${}_4$ layer
• Observation of a 500meV Collective Mode in La${}_{2-x}$Sr${}_x$CuO${}_4$ and Nd${}_2$CuO${}_4$
• Extension of the spin-1/2 frustrated square lattice model: the case of layered vanadium phosphates
• Insights into the High Temperature Superconducting Cuprates from Resonant Inelastic X-ray Scattering
• Ultrashort Lifetime Expansion for Indirect Resonant Inelastic X-ray Scattering
• Pnictides as frustrated quantum antiferromagnet close to a quantum phase transition
• Magnetic Excitations in the High Tc Iron Pnictides
• Electromagnon dispersion probed by inelastic x-ray scattering
• Two-magnon excitations in resonant inelastic x-ray scattering from quantum Heisenberg antiferromagnets
• Second-order quantum corrections for the frustrated, spatially anisotropic, spin-1/2 Heisenberg antiferromagnet on a square lattice
• Observation of phonons with resonant inelastic x-ray scattering
• Theory of two magnon Raman scattering in antiferromagnetic iron pnictides
• Signatures of indirect K-edge resonant inelastic x-ray scattering on magnetic excitations in triangular lattice antiferromagnet

Cited by in corpus (4)

• Resonant inelastic x-ray scattering spectra of spinon, doublon, and quarton excitations of a spin-$\frac{1}{2}$ antiferromagnetic Heisenberg trimer chain
• Discrete Laplacian Thermostat for Spin Systems with Conserved Dynamics
• Chiral Magnons: Mechanisms and Research Progress
• Multimagnon and multispinon $L_3$-edge RIXS spectra of an effective ${\tilde{J}}_1-{\tilde{J}}_2-{\tilde{J}}_3$ square lattice Heisenberg model