| 摘要 |
<p>The magnetoresistive sensor or reproduce head comprises a substrate, on which a thin film, multilayered structure is formed. Alternating electrically conducting, magnetic film layers and non-magnetic film layers are formed such that the magnetic film layers are anti-ferromagnetically coupled across the non-magnetic layers. The anti-ferromagnetic coupling aligns the magnetisation vectors of adjacent consecutive film layers to be anti-parallel when not subjected to any external magnetic field, or the internal magnetic field induced by current flow in it. The multilayer structure exhibits a change in resistivity when subjected to an external magnetic field causing the magnetisation vectors of the adjacent film layers to rotate into a more parallel orientation thereby exhibiting a giant MR effect. A device for producing a current flow through the thin film, structure, in which the magnetic fields generated by the current flow maintain a magnetisation state in which the net component of magnetisation along the axis transverse to that of the current flow of a first set of sandwiched magnetic film layers that are formed on one side of approximately the centre layer is equal in magnitude and opposite in direction by comparison to that of the net component of magnetisation along the axis transverse to that of the current flow of the second set of layers that are formed on the other side of the centre layer. A sensing device senses the variations of resistivity of the MR head w.r.t. an applied magnetic field.</p> |
