Electric field control of magnetism in iron oxide nanoporous thin film
Robbennolt, Shauna (Universitat Autònoma de Barcelona. Departament de Física)
Nicolenco, Aliona (Universitat Autònoma de Barcelona. Departament de Física)
Mercier Fernández, Pau (Universitat Autònoma de Barcelona. Departament de Física)
Auffret, Stéphane (Université Grenoble Alpes. SPINTEC)
Baltz, Vincent (Université Grenoble Alpes. SPINTEC)
Pellicer Vilà, Eva Maria (Universitat Autònoma de Barcelona. Departament de Física)
Menéndez Dalmau, Enric (Universitat Autònoma de Barcelona. Departament de Física)
Sort Viñas, Jordi (Universitat Autònoma de Barcelona. Departament de Física)

Date:	2019
Abstract:	Voltage control of the magnetic properties of oxide thin films is highly appealing to enhance energy efficiency in miniaturized spintronic and magnetoelectric devices. Herein, magnetoelectric effects in electrolyte-gated nanoporous iron oxide films are investigated. Highly porous films were prepared by the evaporation-induced self-assembly of sol-gel precursors with a sacrificial block-copolymer template. For comparison, films with less porosity but analogous crystallographic structure were also prepared using an identical procedure except without the polymer template. The films were found to be 70-85 nm in thickness as measured by scanning electron microscopy and primarily hematite as determined by Raman spectroscopy. The templated (highly porous) films showed a very large magnetoelectric response with a maximum increase in magnetic moment at saturation of a factor of 13 and a noticeable (2-fold) increase of coercivity (after applying -50 V). The nontemplated films also exhibited a pronounced increase of magnetic moment at saturation of a factor of 4, although the coercivity remained unaffected over the same voltage range. Magnetoelectric effects in these latter films were found to be fully reversible in the voltage window ±10 V. The observed changes in magnetic properties are concluded to be magneto-ionically driven with oxygen ion exchange between the iron oxide and the liquid electrolyte, as evidenced from Raman and X-ray photoelectron spectroscopy experiments.
Grants:	European Commission 665919 European Commission 648454 Ministerio de Economía y Competitividad MAT2017-86357-C3-1-R Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-292 European Commission 648454
Note:	Altres ajuts: French National Research Agency (ANR) grant agreement No ANR-15-CE24-0015-01.
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Published in:	ACS applied materials & interfaces, Vol. 11, issue 40 (Oct. 2019) , p. 37338-37346, ISSN 1944-8252

DOI: 10.1021/acsami.9b13483
PMID: 31525887

Postprint 31 p, 1.8 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Group of Smart Nanoengineered Materials, Nanomechanics and Nanomagnetism (Gnm3) > SPIN-PORICS
Articles > Research articles
Articles > Published articles