Exploration of quantum oscillation in antiferromagnetic Weyl semimetal GdSiAl.

Abstract

GdSiAl single crystal has been investigated by means of magnetic and magneto-transport measurements and compared with ab-initio density functional theory (DFT) calculations. Significant non-saturating magnetoresistance reaching ∼ 18% at 12T and 2K was observed, alongside the presence of Shubnikov-de Haas oscillations with the fundamental frequencies 22.09T and 77.33T. Shubnikov-de Haas oscillations provide the information about the nontrivial π Berry phase in GdSiAl with the Fermi surface areas of 0.00211 Å^-2and 0.00739 Å^-2. Angle-dependent magnetoresistance shows anisotropy with θ, exhibiting a maximum at 180^°. The magnetic susceptibility data for H ∥ c and H ⊥ c reveals that the magnetic moments of Gd³⁺ions orders antiferromagnetically below 32K along with an another transition occurs at ∼ 8K, which is consistent with the heat capacity measurements where a distinct λ-shaped anomaly has been observed near antiferromagnetic ordering temperature 32K. The high value of Debye temperature indicates the contribution of acoustic phonons. Electronic structure calculations suggest the existence of nested Fermi surface pockets characterized by nesting wave vectors that closely align with the observed magnetic ordering wave vector. Furthermore, DFT calculations reveal the presence of Weyl nodes in close proximity to the Fermi surface. Our findings from combined experimental and theoretical techniques indicate GdSiAl to be a potential candidate for an antiferromagnetic topological Weyl semimetal.