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Title: Multiple magnetic droplet solitions from exotic spin–orbit torques
Materials with large spin–orbit interactions generate pure spin currents with spin polarizations parallel to the interfacial surfaces that give rise to conventional spin–orbit torques. These spin–orbit torques can only efficiently and deterministically switch magnets with in-plane magnetization. Additional symmetry breaking, such as in non-collinear antiferromagnets, can generate exotic, unconventional spin–orbit torques that are associated with spin polarizations perpendicular to the interfacial planes. Here, we use micromagnetic simulations to investigate whether such exotic spin–orbit torques can generate magnetic droplet solitions in out-of-plane magnetized geometries. We show that a short, high current pulse followed by a lower constant current can nucleate and stabilize magnetic droplets. Through specific current pulse lengths, it is possible to control the number of droplets in such a system, since torques are generated over a large area. Additionally, the nucleation current scales with the out-of-plane component of the spin polarization and is linear as a function of magnetic field strength.  more » « less
Award ID(s):
1720633
PAR ID:
10412207
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
120
Issue:
24
ISSN:
0003-6951
Page Range / eLocation ID:
242407
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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