Band Structure and Charge Ordering of Dirac Semimetal EuAl₄ at Low Temperatures

Journal Article · 24 September 2024 · Physical Review. B

DOI: https://doi.org/10.1103/physrevb.110.125150 · OSTI ID:2447979

Eaton, Andrew  ^[1]; Kuthanazhi, Brinda  ^[2]; Canfield, Paul C.  ^[2]; Schrunk, Benjamin  ^[2]; Jo, Na Hyun  ^[2]; Kushnirenko, Yevhen  ^[2]; O'Leary, Evan  ^[2]; Wang, Lin-Lin  ^[2]; Kaminski, Adam  ^[2]

---

1. Ames Laboratory, and Iowa State University, Ames, IA (United States); Ames Lab
2. Ames Laboratory, and Iowa State University, Ames, IA (United States)

In this article, EuAl₄ is proposed to host a topological Hall state. This material also undergoes four consecutive antiferromagnetic (AFM) transitions upon cooling below T_N1 = 15.4 K in the presence of charge density wave (CDW) order that sets in below T_CDW = 140 K. We use angle-resolved photoemission spectroscopy and density-functional-theory calculations to study how magnetic ordering affects the electronic properties in EuAl₄. Here, we found changes in the band structure upon each of the four consecutive AFM transitions including band splitting, renormalizations, and appearance of new bands forming additional Fermi sheets. In addition we also found significant enhancement of the quasiparticles’ lifetime due to suppression of spin flip scattering, similar to what was previously reported for ferromagnetic EuCd₂As₂. Surprisingly, we observe that most significant changes in electronic properties occur not at T_N1, but instead at the AFM3 to AFM4 transition, which coincides with the largest drop in resistivity.

• Research Organization: Ames Laboratory (AMES), Ames, IA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-07CH11358
• OSTI ID: 2447979
• Report Number(s): IS-J--11-439
• Journal Information: Physical Review. B, Journal Name: Physical Review. B Journal Issue: 12 Vol. 110; ISSN 2469-9950
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English