Spin-polarized supercurrents for spintronics

The year 1911 was remarkable for physics in several respects. Ernest Rutherford postulated the existence of the atomic nucleus, which led him to his atom model; Max Planck introduced the quantum concept of zero-point motion; and Heike Kamerlingh Onnes announced the discovery of superconductivity in mercury below a critical transition temperature (see the article by Dirk van Delft and Peter Kes in PHYSICS TODAY, September 2010, page 38). All three discoveries are equally revolutionary, and all helped pave the way for the transition from a classical to a quantum mechanical picture of our world. © 2011 American Institute of Physics.