Hole doping and electronic correlations in Cr substituted BaFe$$_{2}$$As$$_{2}$$

Journal Article · 21 November 2024 · SciPost Physics

DOI: https://doi.org/10.21468/scipostphys.17.5.141 · OSTI ID:2481288

dos Reis Cantarino, Marli  ^[1]; Pakuszewski, Kevin R. ^[2]; Salzmann, Bjoern ^[3]; Moya, Pedro A. ^[4]; da Silva Neto, Wagner R. ^[4]; Freitas, Gabriel S. ^[2]; Pagliuso, Pascoal G. ^[2]; Adriano, Cris ^[2]; Brito, Walber H. ^[5]; Garcia, Fernando A. ^[6]

---

1. Univ. of Sao Paulo (Brazil); European Synchrotron Radiation Facility (ESRF), Grenoble (France)
2. Univ. of Campinas (UNICAMP), Sao Paulo (Brazil)
3. University of Fribourg (Switzerland)
4. Univ. of Sao Paulo (Brazil)
5. Universidade Federal de Minas Gerais, Belo Horizonte (Brazil)
6. Univ. of Sao Paulo (Brazil); Iowa State Univ., Ames, IA (United States); Ames Laboratory (AMES), Ames, IA (United States)

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. Here, 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_yz-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.

• Research Organization: Ames Laboratory (AMES), Ames, IA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES); São Paulo Research Foundation (FAPESP); Swiss National Science Foundation (SNSF); National Council for Scientific and Technological Development (CNPq)
• Grant/Contract Number: AC02-07CH11358
• OSTI ID: 2481288
• Report Number(s): AL-J--672
• Journal Information: SciPost Physics, Journal Name: SciPost Physics Journal Issue: 5 Vol. 17; ISSN 2542-4653
• Publisher: SciPost FoundationCopyright Statement
• Country of Publication: United States
• Language: English