Abstract: A semiconductor device useable as an electromagnetic isolator. The device has a semiconductor substrate epitaxial with a layer of metal, the latter deposited so as to generate a residual magnetic flux. A waveguiding structure is disposed transverse to the flux effective to cause electromagnetic signals propagating in the waveguiding structure to be attenuated a different amount depending on the direction of propagation. The waveguiding structure is preferably a seminconductor layer deposited epitaxially with the substrate in a channel in the metal.

Abstract: A passivating or insulating layer is described for semiconductor substrat The passivating layer is of the formula Zn.sub.1-x-y M.sub.x Q.sub.y Se:D where 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, M and Q represent different specified elements and D represents a dopant. It is prefered that M and Q are Fe or Mn. The substrate is preferably a III-V semiconductor compound. The devices are capable of rapid switching among other uses.

Abstract: A device and method for magnetizing a material having a magnetic constituent. In a preferred embodiment, a ferromagnetic film and a first film are selectively deposited at first and second locations on the material. The ferromagnetic film is magnetized in a first direction. A voltage source is coupled between the ferromagnetic and first films to enable a spin-polarized current to flow through the material to magnetize the material.