High-Field Raman Scattering in an Antiferromagnet Fe₃BO₆

Abstract

The detailed Raman scattering investigation of the lattice and spin dynamics of a single crystal of the Fe3BO6 antiferromagnet is reported. Azimuthally resolved polarization measurements provided an unambiguous determination of the symmetry of observed excitations. Low-temperature experiments at T=4.2 K allowed us to reduce anharmonic contribution and deconvolute several overlapping phonon modes. Low-frequency measurements have made it possible to find two excitations at 13.1 and 16.6 cm−1, which were assigned to quasi-ferromagnetic and quasi-antiferromagnetic magnon excitations, respectively. The magnetic field applied along the hard-magnetization axis causes energy shifts of these excitations, but no spin-flip transition was observed up to B=30 T.

Keywords

• antiferromagnet
• weak ferromagnetism
• Fe3BO6
• high magnetic field
• Raman scattering
• lattice dynamics