2007 Nobel Prize in Physics

Peter Grünberg of Forschungszentrum Jülich GmbH, Institut für Festkkörperforschung in Germany. Image (c) Forschungszentrum Jülich

Albert Fert of Unité Mixte de Physique CNRS/ THALES, Université Paris-Sud in France. Image (c) CNRS Photolibrary - C. Lebedinsky.
 

 

The 2007 Nobel Prize in Physics will be awarded to Albert Fert (Université Paris-Sud, Orsay, France) and Peter Grünberg (Forschungszentrum Jülich, Germany) for the discovery of giant magnetoresistance, or GMR for short. GMR is the process whereby a tiny magnetic field, such as that of an oriented domain on the surface of a computer hard drive can, when the proper read head is brought nearby, trigger a large change in electrical resistance, thus “reading” the data vested in the magnetic orientation.

This is the heart of modern hard drive technology and makes possible the immense hard-drive data storage industry. Fert and Grünberg pioneered the making of stacks consisting of alternating thin layers of magnetic and non-magnetic atoms needed to produce the GMR effect. GMR is a prominent example of how quantum effects (a large electrical response to a tiny magnetic input) come about through confinement (the atomic layers being so thin.); that is, atoms interact differently with each other when they are confined to a tiny volume or a thin plane.

All these magnetic interactions involve the spin of an electron. Spin is a quantum attribute that shouldn’t be associated too closely in the mind with the electron literally spinning (in the way that a top spins). Still more innovative technology can be expected through quantum effects depending on electrons’ spin.

Most of the electronics industry is based on manipulating the charges of electrons moving through circuits. But the electrons’ spins might also be exploited to gain new control over data storage and processing. Spintronics is the general name for this budding branch of electronics. (Nobel Prize website: http://nobelprize.org/nobel_prizes/physics/laureates/2007/info.html)

Read the Inside Science story
Read AIP Journal Articles from Albert Fert and Peter Grünberg