On the character of phase transitions in ErFeO3

Abstract

An investigation is made of magnetic, magnetoelastic, and elastic properties of erbium orthoferrite in the region of the phase transitions. The first and the second magnetoelastic constants of this orthoferrite, and the first and the second anisotropy constants of the iron sublattice are determined. It is shown that the compensation point in the field H ‖ σ0 is the first-order phase transition. On the basis of magnetization and Young's modulus measurements, and also from symmetry considerations it is concluded that in the temperature range 2 to 4 K Γ12 is the magnetic structure of ErFeO3. [Russian Text Ignored]