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Giant magnetoresistance
quantum mechanical magnetoresistance effect / From Wikipedia, the free encyclopedia
Giant magnetoresistance (GMR) is a very small magnetic effect found in thin layers of iron and other materials. It is used to read and write information in hard drives.
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The GMR effect can be measured when a magnet is used to change the flow of electricity. The 2007 Nobel Prize in physics was awarded to Albert Fert and Peter Grünberg for the discovery of GMR.