Probing putative orbital differentiation effects via Eu2+spin dynamics in Sr1-xEuxFe2As2

Author(s)

Radaelli, M. ; Piva, M. M. ; Souza, J. C. ; Lesseux, G. G. ; Jesus, C. B. R. ; Tobia, D. ; Urbano, R. R. ; Rosa, P. F. S. ; Pagliuso, P. G.

• Document type: Journal article
• Source: PHYSICAL REVIEW B; v. 107, n. 13, p. 8-pg., 2023-04-12.

Abstract

In this work, we report x-ray powder diffraction, elemental analysis, electrical resistivity, magnetic suscep-tibility, specific heat, and electron spin resonance (ESR) in single crystals of Sr1-xEuxFe2As2. We observed a breakdown of the previously reported scaling between the Eu2+ Korringa relaxation rate obtained from ESR and the spin density wave temperature evolution for Sr-rich samples. This result suggests a distinct evolution of the orbital differentiation of the Fe 3d bands along the Sr-based series when compared to the Ba counterpart. We argue that this difference is related to a larger splitting between the structural (tetragonal-to-orthorhombic) and the Fe-driven spin density wave transitions induced by Eu doping in this series. In fact, our results indicate that the two transitions follow an opposite x-Eu dependence for Sr-concentrated samples. Our work shows that Sr1-xEuxFe2As2 series and the comparison with their Ba-based counterparts are exciting platforms to be explored for understanding the interplay among orbital differentiation, magnetism, and structural distortions in the iron pnictides. (AU)

• FAPESP's process: 12/04870-7 - Studies of novel complex and advanced materials
• Grantee: Pascoal Jose Giglio Pagliuso
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/10581-1 - Emergent phenomena in reduced dimension systems
• Grantee: Pascoal Jose Giglio Pagliuso
• Support Opportunities: Special Projects
• FAPESP's process: 18/11364-7 - Magnetic properties of complex systems with non-trivial topology
• Grantee: Jean Carlo Souza
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 20/12283-0 - Scanning tunneling microscopy in topological nontrivial compounds
• Grantee: Jean Carlo Souza
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 15/09701-7 - Growth and characterization of single crystals of (Sr,Ca)Fe2As2 prepared by in flux method
• Grantee: Matheus Radaelli
• Support Opportunities: Scholarships in Brazil - Master