High-field ESR Measurements of YCrO3

High-field electron spin resonance measurements of perovskite compound YCrO3 powder have been performed to obtain the magnetic anisotropy. Isotropic absorption lines of electron paramagnetic resonance, which can be described as single Lorentzian shape, are observed. The g value of paramagnetic state is estimated to be 1.983 at 265 K. Magnitude of D vector of Dzyaloshinskii–Moriya interaction is estimated to be 0.36 K from Moriya’s formula using the obtained g value. Powder patterns of antiferromagnetic resonance (AFMR) with large antiferromagnetic gaps are observed below TN = 140 K. Two antiferromagnetic gaps at zero field have been estimated to be 181 GHz (6.5 T) and 338 GHz (12.1 T), and a spin flop transition field have been estimated to be 3.5 T from widely observed frequency–field diagram at 1.9 K. Although obtained AFMR modes seem to be typical AFMR modes of two sublattice antiferromagnet with triaxial magnetic anisotropy, the obtained zero-field gap is twice as large as the obtained spin flop transition field which suggests the unconventional antiferromagnetic order.