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Title: Even-odd-layer-dependent symmetry breaking in synthetic antiferromagnets
Abstract In this work we examine synthetic antiferromagnetic structures consisting of two, three, and four antiferromagnetic coupled layers, i.e. bilayers, trilayers, and tetralayers. We vary the thickness of the ferromagnetic layers across all structures and, using a macrospin formalism, find that the nearest neighbor exchange interaction between layers is consistent across all structures for a given thickness of the ferromagnetic layer. Our model and experimental results demonstrate significant differences in how the static equilibrium states of even and odd-layered structures evolve as a function of the external field. Even layered structures continuously evolve from a collinear antiferromagnetic state to a spin canted non-collinear magnetic configuration that is mirror-symmetric about the external field. In contrast, odd-layered structures begin with a ferrimagnetic ground state; at a critical field, the ferrimagnetic ground state evolves into a non-collinear state with broken symmetry. Specifically, the magnetic moments found in the odd-layered samples possess stable static equilibrium states that are no longer mirror-symmetric about the external field after a critical field is reached.  more » « less
Award ID(s):
2328787 2117487
PAR ID:
10529396
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Journal of Physics: Condensed Matter
Date Published:
Journal Name:
Journal of Physics: Condensed Matter
Volume:
36
Issue:
37
ISSN:
0953-8984
Page Range / eLocation ID:
375802
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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