Interlayer Couplings Mediated by Antiferromagnetic Magnons

Journal Article · 15 November 2018 · Physical Review Letters

DOI: https://doi.org/10.1103/physrevlett.121.207202 · OSTI ID:1611831

Cheng, Ran ^[1]; Xiao, Di ^[2]; Zhu, Jian-Gang ^[2]

---

1. Carnegie Mellon Univ., Pittsburgh, PA (United States); Univ. of California, Riverside, CA (United States); DOE/OSTI
2. Carnegie Mellon Univ., Pittsburgh, PA (United States)

Collinear antiferromagnets (AFs) support two degenerate magnon excitations carrying opposite spin polarizations, by which magnons can function as electrons in various spin-related phenomena. In an insulating ferromagnet(F)/AF/F trilayer, we explore the magnon-mediated interlayer coupling by calculating the magnon thermal energy in the AF as a function of the orientations of the Fs. Furthermore, the effect manifests as an interlayer exchange interaction and a perpendicular magnetic anisotropy; they both depend on temperature and the AF thickness. In particular, the exchange interaction turns out to be antiferromagnetic at low temperatures and ferromagnetic at high temperatures, whose magnitude can be 10–100 μeV for nanoscale separations, allowing experimental verification.

• Research Organization: Univ. of Washington, Seattle, WA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0012509
• OSTI ID: 1611831
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 20 Vol. 121; ISSN 0031-9007
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English