Spin-glass behaviour with extended short-range ferromagnetic order in U₂RhSi₃

Abstract

For U2RhSi3, which crystallizes in a disordered derivative of the hexagonal AlB2-type structure, we present a detailed investigation of magnetic properties by measurements of AC and DC susceptibility, magnetization, magnetic relaxation, specific heat and electrical resistivity. The results provide evidence for the formation of extended short-range ferromagnetic order at the temperature TC25 K, as indicated by a specific heat anomaly, and for a low-temperature spin-glass state with a freezing temperature Tf = 19.6 K. According to systematic specific heat experiments on isostructural spin-glass systems, short-range ferromagnetic correlations above the spin-freezing temperature are observed in U2RhSi3 (TC25 K, Tf = 19.6 K) and U2CoSi3 (TC10 K, Tf8 K), but not in U2PdSi3 (Tf = 13.5 K) and U2NiSi3 (Tf22 K). Different degrees of structural disorder of transition metal and silicon atoms, both on the same crystallographic site, seem to be the origin for the distinct different magnetic behaviour.

Magnetic Phase Diagram of Ce1−xErxAl2 Intermetallic Compounds

“…It is comparable to those reported for other metallic spin glass systems [13][14][15][16][17]. To investigate the nature of the spin-glass state more deeply, the well-known Vögel-Fulcher law [18] was applied to the data as follows:…”

Ferromagnetic Cluster Glass Phase Embedded in a Paramagnetic and Metallic Host in Non-Uniform Magnetic System CaRu1−xScxO3

“…27 Another feature is that χ FC continues to increase below T m , which also occurs in ferromagnetic cluster glass systems. 28,29 A spin-glass system would show T -independent χ FC below T m (= T ir ). 27 The irreversibility between χ ZFC and χ FC below T ir is a sign of the freezing in spin-glass systems, while the higher T ir than T m in cluster glass systems probably reflects the formation of the clusters.…”

Quantum Interference in Disordered Ferromagnet U2NiSi3

“…The atomic disorder on the latter site leads to a small value of the residual resistivity ratio (RRR) close to 1 and to an enhanced * corresponding author; e-mail: D.Gnida@int.pan.wroc.pl residual resistivity, which amounts to about 390 µΩ cm and 160 µΩ cm for the electric current owing perpendicular and longitudinal to the c-axis, respectively [5,6]. As far as the magnetic properties are concerned, U 2 NiSi 3 was characterized in the early literature reports as a spinglass system with the freezing temperature of 22 K [7] or a re-entrant spin-glass with the ferromagnetic transition at 25 K [8]. Alternatively, it was described as a ferromagnet with the Curie temperature T C = 26 K [9] or T C = 30 K [10].…”