Hole doping and electronic correlations in Cr substituted BaFe2As2

Author(s)

Cantarino, Marli dos Reis ; Pakuszewski, Kevin R. ; Salzmann, Bjoern ; Moya, Pedro H. A. ; Neto, Wagner R. da Silva ; Freitas, Gabriel S. ; Pagliuso, Pascoal G. ; Adriano, Cris ; Brito, Walber H. ; Garcia, Fernando A.

• Document type: Journal article
• Source: SCIPOST PHYSICS; v. 17, n. 5, p. 17-pg., 2024-11-01.

Abstract

For a significant composition range, the suppression of the spin density wave transition temperature ( T SDW ) in Cr- and Mn-substituted BaFe2As2 (CrBFA and MnBFA, respectively) coincides as a function of Cr/Mn content, despite the distinct electronic effects of these substitutions. Additionally, for any Cr/Mn content superconductivity (SC) is absent and this topic is particularly less explored in the case of CrBFA. In this work, we employ angle- resolved photoemission spectroscopy (ARPES) and combined density functional theory plus dynamical mean field theory (DFT+DMFT) to address the evolution of the Fermi surface (FS) and electronic correlations in CrBFA. Our findings reveal that incorporating Cr leads to an effective hole doping of the states near the FS, which is well described within the virtual crystal approximation (VCA). Moreover, analysis of the ARPES spectra of the bands with main d ye-orbital character reveals a fractional scaling of the imaginary part of self-energy as a function of the binding energy, a signature property of Hund's correlations. Our DFT+DMFT calculations support these experimental findings. We conclude that CrBFA is a correlated electron system for which the changes in the FS as a function of Cr are unrelated to the suppression of T SDW . In addition, we suggest that the absence of SC is primarily due to the competition between Cr local moments and the Fe-derived itinerant spin fluctuations. (AU)

• FAPESP's process: 20/13701-0 - ARPES study of the electronic structure in iron-based superconductors
• Grantee: Marli dos Reis Cantarino
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 19/25665-1 - Charge and spin instabilities in unconventional superconductors
• Grantee: Fernando Assis Garcia
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/05150-7 - Electronic structure and magnetic excitations of magnetic superconductors
• Grantee: Marli dos Reis Cantarino
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/10581-1 - Emergent phenomena in reduced dimension systems
• Grantee: Pascoal Jose Giglio Pagliuso
• Support Opportunities: Special Projects