Article comprising exchange-coupled magnetic materials
AssigneeLucent Technologies Inc.
InventorsErnst Michael Gyorgy, deceased, Julia Mae Phillips, Yuri Suzuki, Robert Bruce van Dover
Life of this patent
Estimating the term…
Abstract
Articles according to the invention exemplarily comprise a magnetically hard oxide layer in contact with a magnetically soft oxide layer, with spins in the latter at room temperature exchange-coupled to the (oriented) spins in the former. Exemplarily both materials are ferrimagnetic spinel-type oxides, e.g., CoFe.sub.2 O.sub.4 /(Mn, Zn)Fe.sub.2 O.sub.4. Material combinations according to the invention can be advantageously used in high frequency circuit components such as inductors, since the magnetically soft layer can be in a substantially single domain state even after exposure to a magnetic field of considerable strength, e.g., up to about 500 Oe.
Claims15
An article comprising a first magnetic material layer and a second magnetic material layer having an interface with the first magnetic material layer, associated with each of the first and second magnetic material layers being a spin orientation, the first and second magnetic material layers selected such that, over a temperature range that includes room temperature, exchange coupling causes the spin orientation in at least a portion of the second magnetic material layer that is adjacent to said interface to be a function of the spin orientation of the first magnetic material layer such that a M-H loop of said second magnetic material layer is an asymmetric M-H loop;
- CHARACTERIZED IN THAT
- a) the first and second magnetic material layers comprise a first and a second metal oxide magnetic material, respectively;
- b) said first and second magnetic material layers are epitaxial with each other;
- and
- c) the spin orientation of the first magnetic material layer has a preferred direction that is substantially parallel to said interface.
Dependencies are inferred from the claim text.