Abstract
Perovskite rhodates are characterized by intermediate strengths of both electronic correlation as well as spin-orbit coupling (SOC) and usually behave as moderately correlated metals. A recent publication [Phys. Rev. B 95, 245121 (2017)2469-995010.1103/PhysRevB.95.245121] on epitaxial SrRhO3 thin films reported a bad-metallic behavior and suggested the occurrence of antiferromagnetism below 100 K. We have further studied this SrRhO3 thin film by hard X-ray photoemission spectroscopy and found a very small density of states (DOS) at the Fermi level (EF), which is consistent with the previously reported bad-metallic behavior. However, the absence of DOS persists up to room temperature, which contradicts the explanation of antiferromagnetic transition at ∼100 K. We also employed electronic structure calculations within the framework of density functional theory and dynamical mean-field theory. In contrast to the photoemission results, our calculations indicate metallic behaviors of both bulk SrRhO3 and the SrRhO3 thin film, and a stronger correlation effect was observed in the thin film than that in the bulk. The calculated uniform magnetic susceptibility is substantially larger in the thin film than that in the bulk. We also investigated the role of SOC and found only a moderate modulation of the band structure. Hence SOC is not expected to significantly affect the electronic correlation in SrRhO3. Extrinsic effects of finite-thickness effects beyond our calculations and localization effects may play important roles to induce the negligible spectral weight at EF.
| Original language | English |
|---|---|
| Article number | 085134 |
| Journal | Physical Review B |
| Volume | 101 |
| Issue number | 8 |
| DOIs | |
| State | Published - Feb 15 2020 |
Funding
This work was supported by a Grant-in-Aid for JSPS fellows (Grant No. 17F17327). The HAXPES experiments at SPring-8 were performed under the approval of the Japan Synchrotron Radiation Research Institute (Proposal No. 2018B1449). This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. The work at ORNL was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. M.K. acknowledges support from Grant No. NSF DMR-1733071 and is grateful to the CPHT computer support team. J.M. acknowledges support by the Slovenian Research Agency (ARRS) under Program No. P1-0044. We are thankful to the advice provided by A. Georges, V. R. Cooper, S. F. Yuk, and A. Rastogi, and we also acknowledge the experimental supports provided by K. Ikeda, S. Sakuragi, and H. Kinoshita, as well as enlightening discussion about this work with J. W. Kim and H. Zhou during our beam time at the Advanced Photon Source.