Fingerprints of an orbital-selective Mott phase in the block magnetic state of BaFe2Se3 ladders
Abstract
Resonant Inelastic X-Ray Scattering (RIXS) experiments on the iron-based ladder BaFe2Se3 unveiled an unexpected two-peak structure associated with local orbital (dd) excitations in a block-type antiferromagnetic phase. A mixed character between correlated band-like and localized excitations was also reported. Here, we use the density matrix renormalization group method to calculate the momentum-resolved charge- and orbital-dynamical response functions of a multi-orbital Hubbard chain. Remarkably, our results qualitatively resemble the BaFe2Se3 RIXS data, while also capturing the presence of long-range magnetic order as found in neutron scattering, only when the model is in an exotic orbital-selective Mott phase (OSMP). In the calculations, the experimentally observed zero-momentum transfer RIXS peaks correspond to excitations between itinerant and Mott insulating orbitals. We provide experimentally testable predictions for the momentum-resolved charge and orbital dynamical structures, which can provide further insight into the OSMP regime of BaFe2Se3.
- Publication:
-
Communications Physics
- Pub Date:
- June 2019
- DOI:
- 10.1038/s42005-019-0155-3
- arXiv:
- arXiv:1807.10419
- Bibcode:
- 2019CmPhy...2...64P
- Keywords:
-
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- Nature Communications Physics 2, 64 (2019)