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Title: Periodicity staircase in a centrosymmetric Fe/Gd magnetic thin film system
Abstract

The presence of multiple competing periodicities may result in a system to go through states with modulated periodicities, an example of which is the self-similar staircase-like structure called the Devil’s Staircase. Herein we report on a novel staircase structure of domain periodicity in an amorphous and centrosymmetric Fe/Gd magnetic thin film system wherein the reciprocal space wavevectorQdue to the ordered stripe domains does not evolve continuously, rather exhibits a staircase structure. Resonant X-ray scattering experiments show jumps in the periodicity of the stripe domains as a function of an external magnetic field. When resolved in components, the length-scale step change along Qxwas found to be an integral multiple of a minimum step height of 7 nm, which resembles closely to the exchange length of the system. Modeling the magnetic texture in the Fe/Gd system as an achiral spin arrangement, we have been able to reproduce the steps in the magnetization using a Landau-Lifshitz spin dynamics calculation. Our results indicate that anisotropy and not the dipolar interaction is the dominant cause for the staircase pattern, thereby revealing the effect of achiral magnetism.

 
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NSF-PAR ID:
10484014
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
npj Quantum Materials
Volume:
9
Issue:
1
ISSN:
2397-4648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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