Robust antiferromagnetism in Y$_2$Co$_3$

TL;DR

This paper presents the synthesis, structural characterization, and magnetic properties of Y$_2$Co$_3$, revealing robust antiferromagnetism with complex magnetic behavior and pressure effects, challenging theoretical predictions of magnetic degeneracy.

Contribution

It introduces a solution-growth method for Y$_2$Co$_3$ single crystals and provides detailed experimental and theoretical analysis of its magnetic properties.

Findings

Y$_2$Co$_3$ crystallizes in orthorhombic structure with kagome Co lattices.

Y$_2$Co$_3$ orders antiferromagnetically below 252 K.

Magnetization shows a field-induced spin-flop transition and high robustness of antiferromagnetic order.

Abstract

We report on a solution-growth based method to synthesise single crystals of Y$_2$Co$_3$ and on its structural and magnetic properties. We find that Y$_2$Co$_3$ crystallizes in the La2Ni3-type orthorhombic structure with space group Cmce (No. 64), with Co forming distorted kagome lattices. Y$_2$Co$_3$ orders antiferromagnetically below $T_N$ = 252 K. Magnetization measurements reveal that the moments are primarily aligned along the b axis with evidence for some canting. Band-structure calculations indicate that ferromagnetic and antiferromagnetic orders are nearly degenerate, at odds with experimental results. Magnetization measurements under pressure up to 1 GPa reveal that the N/'eel temperature decreases with the slope of -1.69 K/GPa. We observe a field-induced spin-flop transition in the magnetization measurements at 1.5 K and 21 T with magnetic field along the b direction. The magnetization is not saturated up to 35 T, indicating that the antiferromagnetic ordering in Y$_2$Co$_3$ is quite robust, which is surprising for such a Co-rich intermetallic.