Magnetism in Kitaev Quantum Spin Liquid Candidate RuBr$_3$

TL;DR

This study investigates the magnetic properties of RuBr₃, revealing long-range magnetic order at 34 K and suggesting that replacing Cl with Br weakens Kitaev interactions, offering a way to tune these interactions.

Contribution

It demonstrates that RuBr₃ exhibits magnetic order and that substituting halogens can modulate Kitaev interactions, providing insights into tuning quantum spin liquids.

Findings

Magnetic order in RuBr₃ appears at approximately 34 K.

Muon spectra show well-defined internal magnetic fields.

Kitaev interactions are likely weaker in RuBr₃ compared to RuCl₃.

Abstract

The present studies show that long-range magnetic order takes place in RuBr$_3$ at $\approx$ 34 K. The observations of clear oscillations in the muon time spectra demonstrate the presence of well-defined internal fields at the muon sites. The magnetic ordering appears to be very robust and static suggesting a more conventional nature of magnetic ordering in the RuBr$_3$ system at zero field. Present investigations prove that in RuBr$_3$ the Kitaev interactions are likely to be weakened at zero field in comparison to the $\alpha$-RuCl$_3$ system. This proves that it is possible to tune the Kitaev interactions by replacing Cl with heavier halogen elements such as Br.