Tailorable exchange bias and memory of frozen antiferromagnetic spins in epitaxial CoO(111)/Fe(110) bilayers

We report on exchange bias and interfacial antiferromagnetic spin orientation in epitaxial CoO(111)/Fe(110) bilayers. Our X-ray magnetic linear dichmism and magneto-optic Kerr effect results show that exchange bias sets on in the zero-field-cooled system and is governed by in-plane magnetic state Fe(110) sublayer above Neel temperature of CoO. Uniaxial magnetic anisotropy of Fe layer determines the direction of interfacial frozen antiferromagnetic CoO spins within CoO(111)//Fe(110) sample plane. Choice of the particular magnetic state of Fe sublayer, when passing Neel temperature of CoO, determines both the axis and direction of interfacial antiferromagnetic spins after the sample is cooled and allows for imprinting their +/- 90 degrees and 0/180 degrees alignment within the sample plane.

Automated summary

In this study, exchange bias and interfacial antiferromagnetic spin orientation in epitaxial CoO(111)/Fe(110) bilayers were investigated. Experimental results revealed that exchange bias occurs in the zero-field-cooled system and is influenced by the in-plane magnetic state of the Fe(110) sublayer and the uniaxial magnetic anisotropy of the Fe layer. The specific magnetic state chosen for the Fe sublayer can determine the axis and direction of interfacial antiferromagnetic spins after the sample is cooled.