Magnetic and thermodynamic properties of RMnO$_3$ (R = Pr, Nd)

TL;DR

This study investigates the magnetic and thermodynamic properties of PrMnO3 and NdMnO3, revealing anisotropic behaviors, spin reorientation transitions, and the influence of rare earth ions on their ground states.

Contribution

It provides detailed experimental insights into the anisotropic magnetic behavior and spin reorientation phenomena in PrMnO3 and NdMnO3, highlighting the role of rare earth ions.

Findings

Anisotropic magnetic susceptibility below T_N

Spin-flop transition in NdMnO3 at 110 kOe and 5K

Low-temperature Schottky contributions influenced by magnetic field

Abstract

The ground state properties of the pure perovskite compounds PrMnO$_3$ and NdMnO$_3$ were investigated by magnetization, magnetic AC susceptibility and specific heat measurements. A strongly anisotropic behavior has been detected for temperatures below the antiferromagnetic phase transition $T_N$~100K. The susceptibility and the weak spontaneous ferromagnetic moment appear to be different in both compounds due to different anisotropic rare earth contributions. The specific heat shows strong Schottky type contributions at low temperatures, which for NdMnO$_3$ strongly depend on the magnetic field. A spin reorientation phase transition (spin-flop type) induced by a magnetic field along b axis was observed in NdMnO$_3$ at H~110kOe and T=5K. All results can consistently be explained by anisotropic contributions of the rare earth ions: In PrMnO$_3$ the electronic ground state is determined by a low lying quasidoublet split by the crystal field ~19 K. In NdMnO$_3$ the Kramers doublet is split by an exchange Nd-Mn field (~20K).