2025/07/17 by Jacob W. Fritsky, Fritsky, Jacob W., Hui-Fei Zhai +9 · 1 voice
Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.2507.13243
An important aspect of materials research is the ability to tune different physical properties through controlled alloying. The Ln3M4X13 (Ln = Lanthanide, M = Transition Metal, X = Tetrel) filled skutterudite family is of interest due to the tunability of its constituent components and their effects on physical properties, such as superconductivity and complex magnetism. In this work, Sm3Ru4Sn13-xGex (x = 0 -- 2) was synthesized via excess Sn-flux and characterized using powder and single-crystal X-ray diffraction, magnetometry, X-ray photoelectron spectroscopy, and heat capacity. Sm3Ru4Sn13 and its Ge-solid-solution members crystallize in the Pm-3n space group, which has two unique Wyckoff positions for the tetrel (X) site. In the solid solution members, Ge shows preferential occupancy for one of the two Wyckoff sites, reaching ∼60% and 100% occupancy when x = 1 and 2, respectively. Magnetometry and heat capacity measurements of Sm3Ru4Sn13 indicated antiferromagnetic ordering at TN = 7.3 K. However, Sm3Ru4Sn12Ge and Sm3Ru4Sn11Ge2 showed notably lower-temperature antiferromagnetic phase transitions with substantial peak-broadening at TN = 5.5 K and 4.1 K, respectively. These data suggest that alloying Ge into Sm3Ru4Sn13 causes magnetic frustration within the structure, likely attributable to a change in the density of states from additional Ge p states at the Fermi level. This work demonstrates that preferentially alloying Ge in Sm3Ru4Sn13-xGex allows for more precise tunability of its magnetic structure, elucidating design principles for different quantum phases in intermetallic materials.