摘要 |
The pole includes at least two ferromagnetic layers having different uniaxial anisotropies with the layers in a master/slave relationship, and a nonmagnetic layer disposed between the ferromagnetic layers. The nonmagnetic layer inhibits exchange coupling between the magnetic layers so as to reduce or eliminate edge domains. Magnetic flux is conducted by rotation which can occur at high frequencies and which does not generate any magnetic noise. If the nonmagnetic layer is an electrical insulator, eddy currents are also suppressed. Embodiments are disclosed in which the nonmagnetic layer completely separates and partially separates the ferromagnetic layers in varying configurations. The thickness of the nonmagnetic layer can be estimated with a disclosed inequality.
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