Abstract: The present invention relates to a core composite film for magnetic/nonmagnetic/magnetic multilayer thin film comprising a free magnetic layer, a spacer layer and a pinned magnetic layer. As the core composite film, it may be only the spacer layer is an LB film; and the spacer layer is an organic LB film consisting of materials with insulative, conductive or semiconductive character. As the core composite film, it may also be said free magnetic layer, spacer layer and pinned magnetic layer are all LB films; wherein the pinned magnetic layer and the free magnetic layer are organic films made of magnetic materials. The core composite film can be applied to a magnetic spin valve sensor, which can compose a magnetic induction unit of a magnetic spin valve sensor; and it can also be applied to a magnetic random access memory as a memory cell.

Abstract: The present invention relates to a transistor based on resonant tunneling effect of double barrier tunneling junctions comprising: a substrate, an emitter, a base, a collector and a first and a second tunneling barrier layers; wherein the first tunneling barrier layer is located between the emitter and the base, and the second tunneling barrier layer is located between the base and the collector; furthermore, the junction areas of the tunneling junctions which are formed between the emitter and the base and between the base and collector respectively are 1 ?m2˜10000 ?m2; the thickness of the base is comparable to the electron mean free path of material in the layer; the magnetization orientation is unbounded in one and only one pole of said emitter, base and collector. Because the double-barrier structure is used, it overcomes the Schottky potential between the base and the collector.