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Published on: December 3, 2013
Origin of magnetization decay in spin-dependent tunnel junctions
McCartney1, Dunin-Borkowski, Scheinfein
1Center for Solid State Science, Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287-1704, USA. IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120-6099, USA.
Science (New York, N.Y.)
|November 13, 1999
Summary
Magnetically hard layers in spin-dependent tunnel junctions decay due to fringing fields from soft layers. This instability threatens future information storage device applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Spin-dependent tunnel junctions are key for information storage.
- Instability in the hard magnetic layer causes magnetization decay, hindering device applications.
Purpose of the Study:
- Investigate the cause of hard-layer decay in spin-dependent tunnel junctions.
- Understand the mechanism behind magnetization instability.
Main Methods:
- Lorentz electron microscopy
- Micromagnetic simulations
Main Results:
- Hard-layer decay originates from fringing fields of magnetic domain walls in the soft layer.
- Domain wall motion induces statistical flipping of magnetic moments in the hard layer's grains.
- Progressive disorder and demagnetization of the hard layer observed.
Conclusions:
- Fringing fields from soft layer domain walls are responsible for hard-layer instability.
- This mechanism limits the reliability of spin-dependent tunnel junctions for data storage.
- Further research needed to mitigate this decay for practical applications.
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