Evidence for coexistence of spin-glass and ferrimagnetic phases in BaFe12O19 due to basal plane freezing

We present here the results of low-temperature magnetization and X-ray magnetic circular dichroism studies on single crystals of BaFe12O19 which reveal for the first time the emergence of a spin glass phase, in coexistence with the long-range ordered ferrimagnetic phase, due to the freezing of the basal plane spin component.