Giant magnetoresistive heterogeneous alloys and method of making same

Patent · Thu Jan 01 00:00:00 EST 1998

OSTI ID:871912

Bernardi, Johannes J ^[1]; Thomas, Gareth ^[2]; Huetten, Andreas R ^[1]

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1. Berkeley, CA
2. Oakland, CA

The inventive material exhibits giant magnetoresistance upon application of an external magnetic field at room temperature. The hysteresis is minimal. The inventive material has a magnetic phase formed by eutectic decomposition. The bulk material comprises a plurality of regions characterized by a) the presence of magnetic lamellae wherein the lamellae are separated by a distance smaller than the mean free path of the conduction electrons, and b) a matrix composition having nonmagnetic properties that is interposed between the lamellae within the regions. The inventive, rapidly quenched, eutectic alloys form microstructure lamellae having antiparallel antiferromagnetic coupling and give rise to GMR properties. The inventive materials made according to the inventive process yielded commercially acceptable quantities and timeframes. Annealing destroyed the microstructure lamellae and the GMR effect. Noneutectic alloys did not exhibit the antiparallel microstructure lamellae and did not possess GMR properties.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• DOE Contract Number: AC03-76SF00098
• Assignee: Regents, University of California (Oakland, CA)
• Patent Number(s): US 5824165
• OSTI ID: 871912
• Country of Publication: United States
• Language: English

Related Subjects

giant
magnetoresistive
heterogeneous
alloys
method
inventive
material
exhibits
magnetoresistance
application
external
magnetic
field
temperature
hysteresis
minimal
phase
formed
eutectic
decomposition
bulk
comprises
plurality
regions
characterized
presence
lamellae
separated
distance
mean
free
path
conduction
electrons
matrix
composition
nonmagnetic
properties
interposed
rapidly
quenched
form
microstructure
antiparallel
antiferromagnetic
coupling
rise
gmr
materials
according
process
yielded
commercially
acceptable
quantities
timeframes
annealing
destroyed
effect
noneutectic
exhibit
possess
rapidly quenched
free path
mean free
magnetic field
material comprises
giant magnetoresistive
bulk material
magnetic properties
external magnetic
alloys form
inventive material
eutectic alloy
magnetic phase
material exhibits
conduction electrons
giant magnetoresistance
heterogeneous alloys
exhibits giant
form microstructure
magnetoresistive heterogeneous
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