colossal magnetoresistance

noun

: an extreme change in electrical resistance (as of a conductive material) due to the presence of an applied magnetic field

… other scientists have recently developed materials exhibiting "colossal magnetoresistance," or CMR. The magnetoresistance of a material refers to the percentage change of its electrical resistance in the presence of a magnetic field. The higher the magnetoresistance of a material, the smaller the magnetic field it can distinguish. When materials with higher levels of magnetoresistance are incorporated into future drives' "read heads"—the components that float just above the spinning platters and react to magnetic polarities on their surface—they can determine the magnetic state of smaller areas, thus making possible huge increases in the data-storage capacity of a given surface area.

—Henry Norr, The San Francisco Chronicle, 6 Sept. 2000

Word History

First Known Use

1995, in the meaning defined above

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