Albert Fert Professor, Université Paris-Sud, Orsay, France. Born in 1938.
Photo: © CNRS Photolibrary – C. Lebedinsky

Peter Grünberg Professor, Institut für Festkörperforschung, Forschungszentrum Jülich, Germany. Born in 1939.
Photo: © Forschungszentrum Jülich

A small magnetic change can make a major difference to an electrical current. This is the basis of a responsive sensor that uses giant magnetoresistance. This effect opened the door for a completely new development in electronics, spintronics, and has in the last decade revolutionized techniques for scanning data on hard disks.

Albert Fert and Peter Grünberg discovered the phenomenon of giant magnetoresistance simultaneously but independently in 1988.
Albert Fert and his colleagues created thirty or so magnetic layers sandwiched between non-magnetic material and showed that the influence of an external magnetic field had a major effect on resistance. The group’s first research article coined the concept of giant magnetoresistance. Peter Grünberg’s group saw the same effect when a layer of non-magnetic material was sandwiched between two layers of magnetic material, which is the structure used today in read-out heads.