Abstract
The magnetic interlayer coupling between two magnetic layers separated by an insulator was investigated on Co0.2Fe2.8O4/Fe3O4/MgO/Fe3O4 samples grown by means of molecular beam epitaxy on (001) MgAl2O4 substrates. The samples were designed to observe interlayer coupling of either sign. Hysteresis loop measurements show that the Fe3O4 layers are ferromagnetically coupled in the thickness range 0–45 nm MgO. Below a MgO spacer thickness of 1.3 nm, the coupling strength increases drastically with decreasing MgO thickness and is ascribed to the existence of ferromagnetic bridges through the MgO spacer. The small ferromagnetic coupling above 1.3 nm seems to arise from a magnetostatic coupling due to correlated interface irregularities.
Original language | English |
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Pages (from-to) | 11569-11575 |
Number of pages | 7 |
Journal | Physical Review B: Condensed Matter |
Volume | 55 |
Issue number | 17 |
DOIs | |
Publication status | Published - 1997 |