Magnetic properties of chromium-doped Ni80Fe20 thin films

Alex Devonport, Alena Vishina, Rakesh Singh, Matthew Edwards, Kaiwen Zheng, John Domenico, N. D. Rizzo, Cameron Kopas, Mark van Schilfgaarde, Nathan Newman

Research output: Contribution to journalArticlepeer-review

8 Scopus citations


This paper investigates the properties of thin films of chromium-doped Ni80Fe20 (Permalloy) that could potentially be useful in future low-power magnetic memory technologies. The addition of chromium reduces the saturation magnetization, Ms, which is useful for low-energy switching, but does not significantly degrade the excellent switching properties of the host material even down to 10 K, the lowest temperature measured, in films as thin as 2.5 nm. As an example, an alloy film composed of 15% chromium and 85% Ni80Fe20 has an Ms just over half that of pure Ni80Fe20, with a coercivity Hc less than 4 Oe, an anisotropy field Hk less than 1 Oe, and an easy-axis remanent squareness Mr/Ms of 0.9 (where Mr is the remanent magnetization). Magnetodynamical measurements using a pulsed inductive microwave magnetometer showed that the average Landau Lifshitz damping λ was relatively constant with changing Cr content, but increased significantly for thinner films (λ ≈150 MHz for 11 nm, λ ≈250 MHz for 2.5 nm), and at low bias fields likely due to increased magnetic dispersion. Density functional theory calculations show that chromium reduces Ms by entering the lattice antiferromagnetically; it also increases scattering in the majority spin channel, while adding almost insignificant scattering to the minority channel.

Original languageEnglish (US)
Pages (from-to)193-202
Number of pages10
JournalJournal of Magnetism and Magnetic Materials
StatePublished - Aug 15 2018

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics


Dive into the research topics of 'Magnetic properties of chromium-doped Ni80Fe20 thin films'. Together they form a unique fingerprint.

Cite this