Recent studies in devices comprising metal antiferromagnets have demonstrated the feasibility of a novel spintronic concept in which spin-dependent phenomena are governed by an antiferromagnet instead of a ferromagnet. Here we report experimental observation of the anisotropic magnetoresistance in an antiferromagnetic semiconductor Sr2IrO4. Based on ab initio calculations, we associate the origin of the phenomenon with large anisotropies in the relativistic electronic structure. The antiferromagnet film is exchange coupled to a ferromagnet, which allows us to reorient the antiferromagnet spin-axis in applied magnetic fields via the exchange spring effect. We demonstrate that the semiconducting nature of our AFM electrode allows us to perform anisotropic magnetoresistance measurements in the current-perpendicular-to-plane geometry without introducing a tunnel barrier into the stack. Temperature-dependent measurements of the resistance and anisotropic magnetoresistance highlight the large, entangled tunabilities of the ordinary charge and spin-dependent transport in a spintronic device utilizing the antiferromagnet semiconductor.

] Department of Materials Science and Engineering University of California Berkeley California 94720 USA [2] Centre d'Investigació en Nanociència i Nanotecnologia CSIC ICN 08193 Barcelona Spain [3] Department of Spintronics and Nanoelectronics Institute of Physics ASCR v v i Cukrovarnická 10 162 53 Praha 6 Czech Republic

] Department of Materials Science and Engineering University of California Berkeley California 94720 USA [2] Department of Physics University of California Berkeley California 94720 USA [3] National Center for Electron Microscopy Materials Science Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA [4]

] Department of Spintronics and Nanoelectronics Institute of Physics ASCR v v i Cukrovarnická 10 162 53 Praha 6 Czech Republic [2] School of Physics and Astronomy University of Nottingham Nottingham NG7 2RD UK

] Institut de Ciència de Materials de Barcelona ICMAB CSIC Campus UAB E 08193 Barcelona Spain [2] Experimental Department 2 Max Planck Institute of Microstructure Physics Weinberg 2 D 06120 Halle Germany

Department of Condensed Matter Theory Institute of Physics ASCR v v i Na Slovance 2 182 21 Praha 8 Czech Republic

Department of Materials Science and Engineering University of California Berkeley California 94720 USA

Department of Physics University of California Berkeley California 94720 USA

Department of Spintronics and Nanoelectronics Institute of Physics ASCR v v i Cukrovarnická 10 162 53 Praha 6 Czech Republic

Institut de Ciència de Materials de Barcelona ICMAB CSIC Campus UAB E 08193 Barcelona Spain

National Center for Electron Microscopy Materials Science Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA

References provided by Crossref.org

Anisotropic magnetoresistance in altermagnetic MnTe

Anisotropic magnetoresistance: materials, models and applications

Writing and reading antiferromagnetic Mn2Au by Néel spin-orbit torques and large anisotropic magnetoresistance

Interface-Induced Phenomena in Magnetism

Isothermal anisotropic magnetoresistance in antiferromagnetic metallic IrMn

Antiferromagnetic spintronics