Fig. 3: Magnetic resonance and relaxation.

a Resonance frequency as a function of magnetic field for the low frequency mode of hematite at room temperature. Inset: resonance peak at 255 GHz for a 0.5 mm thick single crystal. b Linewidth as a function of frequency. The blue, brown and green points correspond to literature values from refs. 28,29,30. Shadow red and blue lines correspond to theoretical calculations from two models from Fink et al.31 with (α = 10−6) and without (α = 10−5) a dependence of AFM linewidth on the anisotropy. c Resonance field and linewidth as a function of temperature for an excitation frequency of 127 GHz. Error bars correspond to peak statistics.