AN OPTICALLY ADDRESSED SPIN-POLARISED DIODE

摘要

There is provided a spin polarised diode structure including a semiconductor substrate; and at least one ferromagnetic layer. The diode structure is illuminated with circularly polarised light which stimulates a spin polarised current to flow from the semiconductor into the ferromagnetic layers. The magnitude of the spin polarised current is dependent upon the direction of magnetisation of the ferromagnetic layers relative to the helicity of the illuminating light. In multi ferromagnetic layer structures each ferromagnetic layer is separated from the next by a thin layer of electrically conductive non-magnetic material. The direction of magnetisation of each of the ferromagnetic layers can be independently controlled by the application of an external magnetic field. The spin polarised diode structure could be used as memory elements, read heads, magnetic field sensors or as switches.