We quantitatively compared film-level ferromagnetic resonance (FMR) measurements using standard vector network analyzer (VNA) techniques with device-level FMR measurements for both thermal FMR (T-FMR) and field-swept spin-torque FMR (FS-ST-FMR) techniques on magnetic tunnel junction (MTJ) thin films with in-plane magnetization. The film and FS-ST-FMR device determination of damping α are in agreement; however, α cannot be reliably determined by use of T-FMR device measurements due to bandwidth limitations. The device-level intercept of Hres vs. f is lower than film-level measurements of the effective magnetization (Meff) due to the demagnetizing field and exchange coupling of the patterned free layer. The intercept shows device-to-device variations due to a combination of size variation and local film variations. At the device level, the inhomogeneous broadening (ΔH0) is nearly zero, while in film-level measurements, μ0ΔH0 > 10 mT due to averaging of the local film variations detected explicitly in the intercept of Hres vs. f at the device level. These results suggest that continuous-film and FS-ST-FMR measurements on multiple devices can provide comparable information about thin-film Meff, α, and ΔH0 with minimal interpretation, but caution is necessary when using T-FMR to determine α or ΔH0.
Skip Nav Destination
Article navigation
28 February 2013
Research Article|
February 25 2013
Continuous-film vs. device-level ferromagnetic resonance in magnetic tunnel junction thin films
Eric R. Evarts;
Eric R. Evarts
Magnetics Group, Electromagnetics Division, National Institute of Standards and Technology
, 325 Broadway, Boulder, Colorado 80305, USA
Search for other works by this author on:
Matthew R. Pufall;
Matthew R. Pufall
Magnetics Group, Electromagnetics Division, National Institute of Standards and Technology
, 325 Broadway, Boulder, Colorado 80305, USA
Search for other works by this author on:
William H. Rippard
William H. Rippard
Magnetics Group, Electromagnetics Division, National Institute of Standards and Technology
, 325 Broadway, Boulder, Colorado 80305, USA
Search for other works by this author on:
J. Appl. Phys. 113, 083903 (2013)
Article history
Received:
January 11 2013
Accepted:
February 12 2013
Citation
Eric R. Evarts, Matthew R. Pufall, William H. Rippard; Continuous-film vs. device-level ferromagnetic resonance in magnetic tunnel junction thin films. J. Appl. Phys. 28 February 2013; 113 (8): 083903. https://doi.org/10.1063/1.4793589
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Sign in via your Institution
Sign in via your InstitutionPay-Per-View Access
$40.00
Citing articles via
Related Content
A technique for error estimation of linewidth and damping parameters extracted from ferromagnetic resonance measurements
J. Appl. Phys. (February 2015)
Real-time FMR lorentzian visualization through a novel synchronous VNA-FMR measurement apparatus
Rev. Sci. Instrum. (December 2022)
Tuning the magnetodynamic properties of all-perpendicular spin valves using He+ irradiation
AIP Advances (June 2018)