Magnetic properties of the ferrimagnetic cobaltite CaBaCo4O7

TL;DR

This study systematically investigates the magnetic properties of ferrimagnetic CaBaCo4O7, revealing short-range correlations above T_C and confirming a first-order magnetic transition with specific magnetic moments.

Contribution

It provides new insights into the magnetic behavior and transition nature of CaBaCo4O7, including susceptibility deviations and effective magnetic moments.

Findings

Susceptibility shows deviation below ~360 K indicating short-range correlations.

Effective magnetic moment is 4.5 μ_B per formula unit.

Transition from paramagnetic to ferrimagnetic is first order.

Abstract

The magnetic properties of the ferrimagnetic cobaltite CaBaCo$_4$O$_7$ are systematically investigated. We find that the susceptibility exhibits a downward deviation below $\sim$ 360 K, suggesting the occurrence of short range magnetic correlations at temperature well above $T_C$. The effective moment is determined to be 4.5 $\mu_B$/f.u, which is consistent with that expected for the Co$^{2+}$/Co$^{3+}$ high spin species. Using a criterion given by Banerjee [Phys. Lett. \textbf{12}, 16 (1964)], we demonstrate that the paramagnetic to ferrimagnetic transition in CaBaCo$_4$O$_7$ has a first order character.