Ferromagnetic cluster spin-glass behavior in PrRhSn3

TL;DR

This study reports the discovery of a cluster spin-glass state with ferromagnetic clusters in PrRhSn3, characterized by magnetic, thermal, and transport measurements revealing complex magnetic behavior and strong crystal electric field effects.

Contribution

It provides the first detailed investigation of the magnetic cluster-glass behavior and ferromagnetic clusters in PrRhSn3, supported by comprehensive magnetic, thermal, and transport data.

Findings

Spin-glass behavior with freezing temperature T_f = 4.3 K

Presence of ferromagnetic clusters indicated by specific heat and magnetization anomalies

High Sommerfeld-Wilson ratio R_W ~ 247

Abstract

We report the synthesis, structure, and magnetic and transport properties of a new ternary intermetallic compound PrRhSn3 which crystallizes in LaRuSn3-type cubic structure (space group Pm-3n). At low applied fields the dc magnetic susceptibility exhibits a sharp anomaly below 6~K with an irreversible behavior in zero field cooled (ZFC) and field cooled (FC) susceptibility below 5.5 K. The ac susceptibility exhibits a frequency dependent anomaly revealing a spin-glass behavior with a freezing temperature, T_f = 4.3 K. The observation of spin-glass behavior is further supported by a very slow decay of thermo-remnant magnetization (mean relaxation time tau = 2149 s). However, a small jump at very low field in the isothermal magnetization at 2 K and a weak anomaly in the specific heat near 5.5 K reveal the presence of ferromagnetic clusters. The frequency dependence of the transition temperature T_f in the ac susceptibility obeys the Vogel-Fulcher law, nu = nu_0exp[-E_a/k_B(T_f-T_0)] with activation energy E_a/k_B = 19.1 K. This together with an intermediate value of the parameter delta T_f = Delta T_f/T_f Delta(log nu) = 0.086 provide an evidence for the formation of a cluster-glass state in PrRhSn3. The magnetic contribution of the specific heat reveals a broad Schottky-type anomaly centered around 10 K and the analysis based on the crystal electric field model indicates a singlet ground state. Further, below T_f the magnetic part of the specific heat exhibits a T^{3/2} temperature dependence. The strong influence of the crystal electric field and a T^{3/2} temperature dependence are also seen in the electrical resistivity which reveals a metallic character and a high magnetoresistance. We also obtain a surprisingly large value of Sommerfeld-Wilson ratio R_W ~ 247$.