Connections between resonant inelastic x-ray scattering and complementary x-ray spectroscopies: Probing excitons at the Al K and L$_1$ edges of $\alpha$−Al$_2$O$_3$ - CEA - Université Paris-Saclay
Article Dans Une Revue Physical Review B Année : 2024

Connections between resonant inelastic x-ray scattering and complementary x-ray spectroscopies: Probing excitons at the Al K and L$_1$ edges of $\alpha$−Al$_2$O$_3$

Résumé

We present an ab initio study of neutral core and valence electronic excitations in α-Al2O3 by solving the Bethe-Salpeter equation (BSE) of many-body perturbation theory within an all-electron framework. Calculated spectra at the Al K and L1 edges are in remarkable agreement with available experiments from X-ray absorption (XAS) and X-ray Raman spectroscopy once excitonic effects are taken into account. The combination of the BSE spectra for the two techniques confirms the dipole-forbidden nature of the exciton prepeak as suggested by recent calculations based on densityfunctional theory. Moreover, we make predictions for resonant inelastic X-ray scattering (RIXS) spectra at K and L1 edges, which strikingly fully overlap also beyond an independent-particle picture.The RIXS calculations reveal two distinct regimes as a function of incoming photon energy. Below and at the XAS threshold, we observe Raman-like features, characterised by strong excitonic effects, which we directly compare to peaks in the loss function. Above the XAS threshold, instead, fluorescence features become predominant: RIXS spectra can be well described and analyzed within an independent-particle approximation showing similarity with the X-ray emission spectrum.
Fichier principal
Vignette du fichier
2309.05609v2.pdf (1.43 Mo) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04715694 , version 1 (01-10-2024)

Identifiants

Citer

M. Laura Urquiza, Matteo Gatti, Francesco Sottile. Connections between resonant inelastic x-ray scattering and complementary x-ray spectroscopies: Probing excitons at the Al K and L$_1$ edges of $\alpha$−Al$_2$O$_3$. Physical Review B, 2024, 109 (11), pp.115157. ⟨10.1103/PhysRevB.109.115157⟩. ⟨hal-04715694⟩
0 Consultations
0 Téléchargements

Altmetric

Partager

More