Spin related effects in magnetic mesoscopic systems

Spin effects in transport properties of double‐barrier mesoscopic junctions are analyzed and their possible applications in spintronics devices are discussed. In a general case, external electrodes of the junctions are ferromagnetic and the central electrode is either a nonmagnetic metallic grain or a semiconducting quantum dot. Transport characteristics depend then on magnetic configuration of the system. When the spin relaxation time on the central electrode is sufficiently long, measurable spin effects can also occur in entirely nonmagnetic devices.