Oxide interfaces: Spin-to-charge current conversion

The concept of spintronics (short for spin transport electronics) was first developed in the 1980s and rests on the idea that information can be stored, transferred and processed by means of the spin of the electrons, and that spins can be manipulated not only by magnetic fields but also by electric fields. Among the various pathways towards spintronics proposed so far, the most promising seems to be related to the spin Hall effect: in the presence of spin–orbit interactions, the motion of electrons is coupled to their spin so that a charge current flowing through a specimen characterized by a sizable spin–orbit interaction produces a transverse spin current, polarized in the direction perpendicular to both currents (charge-to-spin conversion). The converse (spin-to-charge conversion) can also be achieved. Edouard Lesne and colleagues1 now report that, taking advantage of the strong spin–orbit coupling existing at certain oxide interfaces such as LaAlO3/SrTiO3, gate-tunable spin-to-charge conversion with unprecedentedly high efficiency is achievable.