Experimental realization of linearly polarized x-ray detected ferromagnetic resonance
Abstract

We present the first theoretical and experimental evidence of time-resolved dynamic x-ray magnetic linear dichroism (XMLD) measurements of GHz magnetic precessions driven by ferromagnetic resonance in both metallic and insulating thin films. Our findings show a dynamic XMLD in both ferromagnetic Ni80Fe20and ferrimagnetic Ni0.65Zn0.35Al0.8Fe1.2O4for different measurement geometries and linear polarizations. A detailed analysis of the observed signals reveals the importance of separating different harmonic components in the dynamic signal in order to identify the XMLD response without the influence of competing contributions. In particular, RF magnetic resonance elicits a large dynamic XMLD response at the fundamental frequency under experimental geometries with oblique x-ray polarization. The geometric range and experimental sensitivity can be improved by isolating the 2ωFourier component of the dynamic response. These results illustrate the potential of dynamic XMLD and represent a milestone accomplishment toward the study of GHz spin dynamics in systems beyond ferromagnetic order.

Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10361773
Journal Name:
New Journal of Physics
Volume:
24
Issue:
1
Page Range or eLocation-ID:
Article No. 013030
ISSN:
1367-2630
Publisher:
IOP Publishing
National Science Foundation
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2. Abstract

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