Crystal field splitting in Sr${}_{n+1}$Ir${}_n$O${}_{3n+1}$ ($n$ = 1, 2) iridates probed by x-ray Raman spectroscopy

Abstract

Non-resonant Raman spectroscopy in the hard X-ray regime has been used to explore the electronic structure of the first two members of the Ruddlesden-Popper series Sr${}_{n+1}$Ir${}_n$O${}_{3n+1}$ of iridates. By tuning the photon energy transfer around 530 eV we have been able to explore the oxygen K near edge structure with bulk sensitivity. The angular dependence of the spectra has been exploited to assign features in the 528-535 eV energy range to specific transitions involving the Ir 5d orbitals. This has allowed us to extract reliable values for both the t2g-eg splitting arising from the cubic component of the crystal field (10Dq), in addition to the splitting of the eg orbitals due to tetragonal distortions. The values we obtain are (3.8, 1.6) eV and (3.55, 1.9) eV for Sr${}_2$IrO${}_4$ and Sr${}_3$Ir${}_2$O${}_7$, respectively.

6 pages, 4 figures, 2 tables

References in corpus (10)

• Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4
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• Electronic structures of layered perovskite Sr2MO4 (M=Ru, Rh, and Ir)
• On the magnetic structure of Sr3Ir2O7: an x-ray resonant scattering study
• Spin correlated electronic state on the surface of a spin-orbit Mott system (Layered Iridates)

Cited by in corpus (4)

• Evidence of quantum dimer excitations in Sr${}_3$Ir${}_2$O${}_7$
• High-pressure insulator-to-metal transition in Sr${}_3$Ir${}_2$O${}_7$ studied by x-ray absorption spectroscopy
• Possibility to realize spin-orbit-induced correlated physics in iridium fluorides
• A $j_{\mathrm{eff}}=1/2$ pseudospinon continuum in CaIrO${}_3$