Influence of Quantum Magnetic Fluctuations on the Transport Properties of Ce₂Ge₂Mg

Ce₂Ge₂Mg crystallizes in a layered structure where the magnetic Ce ions are in isolated layers, forming the Shastry–Sutherland lattice within the tetragonal a–b plane, while the Ge and Mg atoms occupy interstitial positions [1–3]. This compound is part of the broader R₂T₂X (R = rare earth, T = transition metal, X = main group element) family of materials which host a wide variety of correlated electron physics [3]. Ce₂Ge₂Mg is particularly noteworthy within this family because its magnetic f-electrons lie below the Fermi level, enabling investigation of localized f-orbital behavior in a metallic environment.

We have made measurements of the Hall resistance of Ce₂Ge₂Mg in a variety of orientations. In this talk, I will discuss these measurements, their implications, and how they relate to previous measurements on magnetoresistance, specific heat, and ordered magnetic structure, all of which suggest the presence of strong quantum magnetic fluctuations.