Nanomagnetism of Magnetoelectric Granular Thin-Film Antiferromagnets

Thin film magnetoelectric antiferromagnets (AF) have potential to revolutionize spintronics due to their inherently magnetic-field stable magnetic order and high-frequency operation. To explore their application potential, it is necessary to understand modifications of the magnetic properties of AF thin films with respect to their bulk counterparts. We will outline our developments of zero-offset anomalous Hall magnetometry [1] applied to study the physics of insulating magnetoelectric Cr2O3 antiferromagnets. The analysis of the transport data is backed up by the real space imaging of AF domain patterns using NV microscopy [2,3]. Considering grainy morphology of thin films, we address questions regarding the change of the intergranular exchange [3], criticality behavior and switching of the order parameter [1] and physics of the readout signal in α-Cr2O3 interfaced with Pt [4]. The possibility to read-out the antiferromagnetic order parameter all-electrically enabled a new recording concept of antiferromagnetic magnetoelectric random access memory (AF-MERAM) [2].
[1] T. Kosub et al., Phys. Rev. Lett. 115, 097201 (2015).
[2] T. Kosub et al., Nat. Commun. 8, 13985 (2017).
[3] P. Appel et al., Nano Lett. 19, 1682 (2019)
[4] R. Schlitz et al., Appl. Phys. Lett. 112, 132401 (2018).