Magneto-Seebeck microscopy of domain switching in collinear antiferromagnet CuMnAs

Janda, T.; Godinho, J.; Ostatnicky, T.; Pfitzner, E.; Ulrich, G.; Hoehl, A.; Reimers, S.; �ob�?, Z.; Metzger, T.; Reichlov�, H.; Nov�k, V.; Campion, R. P.; Heberle, J.; Wadley, P.; Edmonds, K. W.; Amin, O. J.; Chauhan, J. S.; Dhesi, S. S.; Maccherozzi, F.; Otxoa, R. M.; Roy, P. E.; Olejn�k, K.; N?mec, P.; Jungwirth, T.; Kaestner, B.; Wunderlich, J.

Abstract

Antiferromagnets offer spintronic device characteristics unparalleled in ferromagnets owing to their lack of stray fields, THz spin dynamics, and rich materials landscape. Microscopic imaging of antiferromagnetic domains is one of the key prerequisites for understanding physical principles of the device operation. However, adapting common magnetometry techniques to the dipolar-field-free antiferromagnets has been a major challenge. Here we demonstrate in a collinear antiferromagnet a thermoelectric detection method by combining the magneto-Seebeck effect with local heat gradients generated by scanning far-field or near-field techniques. In a 20-nm epilayer of uniaxial CuMnAs we observe reversible 180∘ switching of the Néel vector via domain wall displacement, controlled by the polarity of the current pulses. We also image polarity-dependent 90∘ switching of the Néel vector in a thicker biaxial film, and domain shattering induced at higher pulse amplitudes. The antiferromagnetic domain maps obtained by our laboratory technique are compared to measurements by the established synchrotron-based technique of x-ray photoemission electron microscopy using x-ray magnetic linear dichroism.

Citation

Janda, T., Godinho, J., Ostatnicky, T., Pfitzner, E., Ulrich, G., Hoehl, A., …Wunderlich, J. (2020). Magneto-Seebeck microscopy of domain switching in collinear antiferromagnet CuMnAs. Physical Review Materials, 4(9), Article 094413. https://doi.org/10.1103/physrevmaterials.4.094413

• Journal Article Type: Article
• Acceptance Date: Aug 12, 2020
• Online Publication Date: Sep 28, 2020
• Publication Date: Sep 28, 2020
• Deposit Date: Nov 9, 2020
• Publicly Available Date: Nov 9, 2020
• Journal: Physical Review Materials
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 4
• Issue: 9
• Article Number: 094413
• DOI: https://doi.org/10.1103/physrevmaterials.4.094413
• Public URL: https://nottingham-repository.worktribe.com/output/5030600
• Publisher URL: https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.4.094413