Spintronics with magnetoelectric antiferromagnetic thin films

Thin film 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 and magnetoelectric responses of AF thin films with respect to their bulk counterparts. Considering grainy morphology of thin films, questions regarding the change of the intergranular exchange, criticality behavior and switching of the order parameter need to be addressed.
Our approach is based on the electron transport characterization of magnetic responses of thin film metallic (IrMn) and insulating (α-Cr2O3) antiferromagnets [1-3]. To access minute uncompensated surface magnetization, we rely on zero-offset Hall magnetometry [2]. To build a reliable description of the material properties, the analysis of the transport data is backed up by structural characterization and real space imaging of AF domain patterns using NV microscopy [2].
The fundamental understanding of the magnetic microstructure of magnetoelectric α-Cr2O3 thin films and the possibility to read-out its AF order parameter all-electrically allowed us to put forth a new recording concept where a magnetoelectric memory cell is addressed without using a ferromagnet [1].
[1] T. Kosub et al., Nat. Commun. 8, 13985 (2017).
[2] T. Kosub et al., Phys. Rev. Lett. 115, 097201 (2015).
[3] R. Schlitz et al., Appl. Phys. Lett. 112, 132401 (2018).