Low temperature magnetic and dielectric properties of LnBaCuFeO5 (Ln = Nd, Eu, Gd, Ho and Yb)

TL;DR

This study investigates the structural, magnetic, and dielectric properties of LnBaCuFeO5 compounds with different rare earth elements, revealing magnetic transitions and dielectric behaviors with minimal magneto-dielectric coupling.

Contribution

It provides new insights into the temperature-dependent magnetic and dielectric properties of LnBaCuFeO5 compounds with various rare earth ions.

Findings

EuBaCuFeO5 exhibits an antiferromagnetic transition near 120 K.

Glassy electric dipole dynamics occur below 100 K in EuBaCuFeO5.

Dielectric anomalies are minimal, with a weak feature in HoBaCuFeO5 around 54 K.

Abstract

The layered perovskite compounds are interesting due to their intriguing physical properties. In this article we report the structural, magnetic and dielectric properties of LnBaCuFeO5 (Ln=Nd, Eu, Gd, Ho and Yb). The structural parameters decrease from Nd to Yb due to the decrease in the ionic radii of the rare earth ions. An antiferromagnetic transition is observed for EuBaCuFeO5 near 120 K along with the glassy dynamics of the electric dipoles below 100 K. The magnetic transition is absent in other compounds, which may be due to the dominance of the magnetic moment of the rare earth ions. The dielectric constant does not show any anomaly, except in the case of HoBaCuFeO5 where it shows a weak frequency dependence around 54 K. These compounds show a significant enhancement of dielectric constant at high temperatures which have been attributed to Maxwell-Wagner effect. However, no significant magneto-dielectric coupling has been observed in these layered perovskites.