ABSTRACT
Spintronics is a merging between magnetism and microelectronics.
Magnetic tunnel junctions constitute key basic elements in spin-
tronic circuits. Their resistance depends on their magnetic configu-
ration (magnetoresistance), which can be used to store information.
Since they combine non-volatility with hardness to radiations, low-
power consumption, speed, density and quasi-infinite endurance,
they may replace parts of the memory hierarchy and allow con-
ceiving a normally-OFF/instant-ON low-power electronics (More
than Moore). In this chapter, spintronic phenomena, technology and
devices are presented as well as their use in memory, logic and RF
applications.