Spin Electronics - or Spintronics - can be defined as a new type of electronics harnessing the influence of the electron spin* on the electrical conduction. Its first impact on the Information and Communication Technologies came from the discovery of the Giant Magnetoresistance (GMR) in 1988. Rapidly applied to the read heads of the hard disc drives, the GMR led to a very large increase of the capacity of the discs. Spintronics became an active field of research which revealed other spin-induced phenomena and brought in other applications. An example of recent application is the use of the spin dependent tunnelling in the non-volatile random access memories called Magnetic-RAM. The Magnetic-RAMs of the first generation are mainly used in the avionic and space technologies for their insensitivity to radiations. The Spin-Tranfer-RAMs (ST-RAMs) developed today are expected to reduce greatly the energy consumption of the computers and to impact significantly their technology. The Spin Transfer Oscillators (STOs) are also promising for telecommunications.
At longer term, spintronics is foreseen in the electronic industry roadmap as one of the main candidates to go beyond the limits of conventional electronics in the so-called “beyond CMOS” perspective. For example, novel concepts for logic circuits are based on the transport and processing of “spin information” coded by pure spin currents. Graphene, a single layer of carbon atoms, is though to be the ideal material for this new type of logic devices with groundbreaking advantages in terms of speed and ultra-low energy consumption.
The lecture will present in parallel the physical concepts of the spintronic phenomena and their use in technology.
* The spin can be shortly described as the small magnet carried by the electrons.