Chirally coupled nanomagnets

• Published in: Science (American Association for the Advancement of Science) Vol. 363; no. 6434; pp. 1435 - 1439
• Main Authors: Luo, Zhaochu, Dao, Trong Phuong, Hrabec, Aleš, Vijayakumar, Jaianth, Kleibert, Armin, Baumgartner, Manuel, Kirk, Eugenie, Cui, Jizhai, Savchenko, Tatiana, Krishnaswamy, Gunasheel, Heyderman, Laura J., Gambardella, Pietro
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 29.03.2019; The American Association for the Advancement of Science
• Subjects: Antiferromagnetism; Cobalt; Couplings; Domain walls; Electric control; Hypothetical particles; Logic circuits; Logical Thinking; Magnetic domains; Magnets; Memory devices; Particle theory; Platinum; Spintronics; Topology
• ISSN: 0036-8075; 1095-9203; 1095-9203
• DOI: 10.1126/science.aau7913

Magnetically coupled nanomagnets have multiple applications in nonvolatile memories, logic gates, and sensors. The most effective couplings have been found to occur between the magnetic layers in a vertical stack. We achieved strong coupling of laterally adjacent nanomagnets using the interfacial Dzyaloshinskii-Moriya interaction. This coupling is mediated by chiral domain walls between out-of-plane and in-plane magnetic regions and dominates the behavior of nanomagnets below a critical size. We used this concept to realize lateral exchange bias, field-free current-induced switching between multistate magnetic configurations as well as synthetic antiferromagnets, skyrmions, and artificial spin ices covering a broad range of length scales and topologies. Our work provides a platform to design arrays of correlated nanomagnets and to achieve all-electric control of planar logic gates and memory devices.