Back to search

NANO2021-Nanoteknologi og nye materiale

Novel Nanomagnetic Oxide Composites: Giant Exchange Bias Storage Devices

Awarded: NOK 5.8 mill.

Project Number:

189721

Application Type:

Project Period:

2009 - 2014

Subject Fields:

Partner countries:

We have studied the magnetic and chemical properties of the hematite-ilmenite (Fe2O3-FeTiO3) solid solution, on natural and synthetic samples. Our understanding of the properties of this solid solution is extensive and we have continually found novel prop erties such as high-temperature magnetic stability (McEnroe et al. 2001, 2002,2004, 2007), 'Lamellar Magnetism'(Robinson et al. Nature 2002; Am Min. 2004) and giant exchange bias (McEnroe et al. Nature Nanotechnology 2007; Harrison et al. PRL 2007; Fabian et al. EPSL 2008). The last is the first report of exchange between two antiferromagnetic (AF) systems. This anomalous exchange is due to the interaction between interface moments and the two AF materials, ilmenite and hematite. Our revised phase diagram s of the hem-ilm solid solution (Harrison, 2006, McEnroe et al. 2007, Burton et al.2008), incorporating experimental room- and low-temperature magnetic behavior with theoretical phase constraints, are the most up-to date and thorough analyses of this syst em. Experimental work evaluating effects of pressure (McEnroe et al. 2004) yields important insights. We bring together the strengths of fundamental understanding of phase petrology, magnetic and chemical properties of this solid solution (NGU), with expe rtise in thin film production by the ADL method at UiO and with TEM expertise from our MATERA partner at Münster. Hematite-ilmenite thin films have been proposed as one of the new high-temperature magnetic semiconductors (Chambers et al., 2006). More imp ortant, because intergrowths in this system have shown the largest exchange bias ever reported, over 13.34 T, this system offers possibilities for designer thin films with novel magnetic properties. We have repeatedly shown that these intergrowths have ex treme stability and Néel T's higher than single-phase compositions.

Publications from Cristin

No publications found

No publications found

No publications found

No publications found

Funding scheme:

NANO2021-Nanoteknologi og nye materiale