Magnetic ground state and 2D behavior in pseudo-Kagome layered system Cu3Bi(SeO3)2O2Br

TL;DR

This study investigates the magnetic properties of Cu3Bi(SeO3)2O2Br, revealing complex layered antiferromagnetic order, field-induced transitions, and XY-like behavior in a quasi-2D kagome-like system.

Contribution

It provides detailed experimental insights into the magnetic ground state and anisotropic behavior of a pseudo-Kagome layered compound, including exchange interactions and field-induced transitions.

Findings

Antiferromagnetic order develops below 27.4 K.

A metamagnetic transition occurs at ~0.8 T with layer flipping.

The system exhibits XY-like magnetic characteristics.

Abstract

Anisotropic magnetic properties of a layered kagome-like system Cu3Bi(SeO3)2O2Br have been studied by bulk magnetization and magnetic susceptibility measurements as well as powder and single-crystal neutron diffraction. At T_N = 27.4 K the system develops an alternating antiferromagnetic order of (ab) layers, which individually exhibit canted ferrimagnetic moment arrangement, resulting from the competing ferro- and antiferro-magnetic intralayer exchange interactions. A magnetic field B_C ~ 0.8 T applied along the c axis (perpendicular to the layers) triggers a metamagnetic transition, when every second layer flips, i.e., resulting in a ferrimagnetic structure. Significantly higher fields are required to rotate the ferromagnetic component towards the b axis (~7 T) or towards the a axis (~15 T). The estimates of the exchange coupling constants and features indicative of an XY character of this quasi-2D system are presented.