NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Determination of the exchange constant of Tb0.3Dy0.7Fe2 by broadband ferromagnetic resonance spectroscopy
Published
Author(s)
Daniel B. Gopman, June W. Lau, Kotekar P. Mohanchandra, Kyle Wetzlar, Greg Carman
Abstract
We present measurements of the exchange stiffness D and the exchange constant A of a sputtered 80 nm Tb0.3Dy0.7Fe2 film. Using a broadband ferromagnetic resonance setup in a wide frequency range from 10 GHz to 50 GHz, multiple perpendicular standing spin-wave resonances were observed with the external static magnetic field applied inplane. The field corresponding to the strongest resonance peak at each frequency is used to determine the effective magnetization, the gfactor and the Gilbert damping. Furthermore, the dependence of spin-wave mode on field-position is observed for several frequencies. The analysis of spin-wave resonance spectra at multiple frequencies allows us to determine D = (2.79 ± 0.02) · 10−17 T · m2 for an 80 nm thick film. From this, we calculated A = (9.1 ± 0.1)pJ · m−1.
Gopman, D.
, Lau, J.
, Mohanchandra, K.
, Wetzlar, K.
and Carman, G.
(2016),
Determination of the exchange constant of Tb0.3Dy0.7Fe2 by broadband ferromagnetic resonance spectroscopy, Physical Review B, [online], https://doi.org/10.1103/PhysRevB.93.064425
(Accessed October 2, 2025)