Demonstration of resonant inelastic X-ray scattering as a probe of exciton-phonon coupling

Abstract

Resonant inelastic X-ray scattering (RIXS) is a promising technique for obtaining electron-phonon coupling constants. However, the ability to extract these coupling constants throughout the Brillouin zone for crystalline materials remains limited. To address this need, we developed a Green's function formalism to capture electron-phonon contributions to core-level spectroscopies without explicitly solving the full vibronic problem. Our approach is based on the cumulant expansion of the Green's function combined with many-body theory calculated vibrational coupling constants. The methodology is applied to X-ray photoemission spectroscopy, X-ray absorption spectroscopy (XAS), and RIXS. In the case of the XAS and RIXS, we use a 2-particle exciton Green's function, which accounts implicitly for particle-hole interference effects that have previously proved difficult. To demonstrate the methodology and gain a deeper understanding of the experimental technique, we apply our formalism to small molecules, for which unambiguous experimental data exist. This comparison reveals that the vibronic coupling constant probed by RIXS is in fact related to exciton-phonon coupling rather than electron-phonon coupling, challenging the conventional interpretation of the experiment.

References in corpus (18)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Electron-phonon interactions from first principles
• Scanning tunneling spectroscopy of high-temperature superconductors
• {\it Ab--initio} finite temperature excitons
• Efficient implementation of core-excitation Bethe Salpeter equation calculations
• Directly characterizing the relative strength and momentum dependence of electron-phonon coupling using resonant inelastic x-ray scattering
• Quasiparticles and phonon satellites in spectral functions of semiconductors and insulators: Cumulants applied to full first principles theory and Fröhlich polaron
• Band structures of plasmonic polarons
• Ubiquitous strong electron phonon coupling at the interface of FeSe/SrTiO3
• Electron-lattice interactions strongly renormalize the charge transfer energy in the spin-chain cuprate Li${}_2$CuO${}_2$
• Real time cumulant approach for charge transfer satellites in x-ray photoemission spectra
• Revisiting the origin of satellites in core level photoemission of transparent conducting oxides: the case of $n$-doped SnO${}_2$
• Particle-hole cumulant approach for inelastic losses in x-ray spectra
• Observation of phonons with resonant inelastic x-ray scattering
• Cumulant expansion for phonon contributions to the electron spectral function
• Ab Initio Approach to Second-order Resonant Raman Scattering Including Exciton-Phonon Interaction
• The GW plus cumulant method and plasmonic polarons: application to the homogeneous electron gas
• Spin-Hall Conductivity in Electron-Phonon Coupled Systems

Cited by in corpus (21)

• Experimental Determination of Momentum-Resolved Electron-Phonon Coupling
• Determining the Electron-Phonon Coupling in Superconducting Cuprates by Resonant Inelastic X-ray Scattering: Methods and Results on Nd${}_{1+x}$Ba${}_{2-x}$Cu${}_3$O${}_{7-\delta }$
• Exploring Quantum Materials with Resonant Inelastic X-Ray Scattering
• Elementary excitations of single-photon emitters in hexagonal Boron Nitride
• High-resolution resonant inelastic x-ray scattering study of the electron-phonon coupling in honeycomb $\alpha$-Li${}_2$IrO${}_3$
• Generalization of the Franck-Condon model for phonon excitations by resonant inelastic X-ray scattering
• Multi-code Benchmark on Simulated Ti K-edge X-ray Absorption Spectra of Ti-O Compounds
• Description of resonant inelastic x-ray scattering in correlated metals
• Probing electron-phonon interactions away from the Fermi level with resonant inelastic x-ray scattering
• Doping-dependence of the electron-phonon coupling in two families of bilayer superconducting cuprates
• Excitation Pathways in Resonant Inelastic X-Ray Scattering of Solids
• Disparate exciton-phonon couplings for zone center and boundary phonons in solid-state graphite
• All-electron many-body approach to resonant inelastic x-ray scattering
• Machine learning in interpretation of electronic core-level spectra
• Beyond the single-site approximation modeling of electron-phonon coupling effects on resonant inelastic X-ray scattering spectra
• Pseudopotential Bethe-Salpeter calculations for shallow-core x-ray absorption near-edge structures: excitonic effects in Al2O3
• Theory of electron-phonon interactions in extended correlated systems probed by resonant inelastic x-ray scattering
• Resonant inelastic x-ray scattering study of doping and temperature dependence of low-energy excitations in La${}_{1-x}$Sr${}_x$VO${}_3$
• Decoupling of Static and Dynamic Charge Correlations revealed by Uniaxial Strain in a Cuprate Superconductor
• Persistence of small polarons into the superconducting phase of Ba${}_{1-x}$K${}_x$BiO${}_3$
• The influence of phonon symmetry and electronic structure on the electron-phonon coupling momentum dependence in cuprates