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Title: Hydroxide-based magneto-ionics: electric-field control of a reversible paramagnetic-to-ferromagnetic switch in α-Co(OH) 2 films
Magneto-ionics has emerged as a promising approach to manipulate magnetic properties, not only by drastically reducing power consumption associated with electric current based devices but also by enabling novel functionalities. To date, magneto-ionics have been mostly explored in oxygen-based systems, while there is a surge of interest in alternative ionic systems. Here we demonstrate highly effective hydroxide-based magneto-ionics in electrodeposited α-Co(OH) 2 films. The α-Co(OH) 2 , which is a room temperature paramagnet, is switched to ferromagnetic after electrolyte gating with a negative voltage. The system is fully, magnetically reversible upon positive voltage application. The origin of the reversible paramagnetic-to-ferromagnetic transition is attributed to the ionic diffusion of hydroxyl groups, promoting the formation of metallic cobalt ferromagnetic regions. Our findings demonstrate one of the lowest turn-on voltages reported for propylene carbonate gated experiments. By tuning the voltage magnitude and sample area we demonstrate that the speed of the induced ionic effect can be drastically enhanced.  more » « less
Award ID(s):
2151809 1933527 1828420 1659532
NSF-PAR ID:
10398329
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
10
Issue:
45
ISSN:
2050-7526
Page Range / eLocation ID:
17145 to 17153
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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