TY - JOUR
T1 - Large Magnetoelectric Effects in Electrodeposited Nanoporous Microdisks Driven by Effective Surface Charging and Magneto-Ionics
AU - Navarro-Senent, Cristina
AU - Fornell, Jordina
AU - Isarain-Chávez, Eloy
AU - Quintana, Alberto
AU - Menéndez, Enric
AU - Foerster, Michael
AU - Aballe, Lucía
AU - Weschke, Eugen
AU - Nogués, Josep
AU - Pellicer, Eva
AU - Sort, Jordi
PY - 2018/12/26
Y1 - 2018/12/26
N2 - Copyright © 2018 American Chemical Society. A synergetic approach to enhance magnetoelectric effects (i.e., control of magnetism with voltage) and improve energy efficiency in magnetically actuated devices is presented. The investigated material consists of an ordered array of Co-Pt microdisks, in which nanoporosity and partial oxidation are introduced during the synthetic procedure to synergetically boost the effects of electric field. The microdisks are grown by electrodeposition from an electrolyte containing an amphiphilic polymeric surfactant. The bath formulation is designed to favor the incorporation of oxygen in the form of cobalt oxide. A pronounced reduction of coercivity (88%) and a remarkable increase of Kerr signal amplitude (60%) are observed at room temperature upon subjecting the microdisks to negative voltages through an electrical double layer. These large voltage-induced changes in the magnetic properties of the microdisks are due to (i) the high surface-area-to-volume ratio with ultranarrow pore walls (sub-10 nm) that promote enhanced electric charge accumulation and (ii) magneto-ionic effects, where voltage-driven O 2- migration promotes a partial reduction of CoO to Co at room temperature. This simple and versatile procedure to fabricate patterned "nano-in-micro" magnetic motifs with adjustable voltage-driven magnetic properties is very appealing for energy-efficient magnetic recording systems and other magnetoelectronic devices. ©
AB - Copyright © 2018 American Chemical Society. A synergetic approach to enhance magnetoelectric effects (i.e., control of magnetism with voltage) and improve energy efficiency in magnetically actuated devices is presented. The investigated material consists of an ordered array of Co-Pt microdisks, in which nanoporosity and partial oxidation are introduced during the synthetic procedure to synergetically boost the effects of electric field. The microdisks are grown by electrodeposition from an electrolyte containing an amphiphilic polymeric surfactant. The bath formulation is designed to favor the incorporation of oxygen in the form of cobalt oxide. A pronounced reduction of coercivity (88%) and a remarkable increase of Kerr signal amplitude (60%) are observed at room temperature upon subjecting the microdisks to negative voltages through an electrical double layer. These large voltage-induced changes in the magnetic properties of the microdisks are due to (i) the high surface-area-to-volume ratio with ultranarrow pore walls (sub-10 nm) that promote enhanced electric charge accumulation and (ii) magneto-ionic effects, where voltage-driven O 2- migration promotes a partial reduction of CoO to Co at room temperature. This simple and versatile procedure to fabricate patterned "nano-in-micro" magnetic motifs with adjustable voltage-driven magnetic properties is very appealing for energy-efficient magnetic recording systems and other magnetoelectronic devices. ©
KW - Co-Pt alloy
KW - magneto-ionic effects
KW - magnetoelectric actuation
KW - nanoporous material
KW - patterned microstructures
U2 - 10.1021/acsami.8b17442
DO - 10.1021/acsami.8b17442
M3 - Article
C2 - 30520631
SN - 1944-8244
VL - 10
SP - 44897
EP - 44905
JO - ACS Applied Materials & Interfaces
JF - ACS Applied Materials & Interfaces
ER -