The efficiency and the demagnetization field of a general Halbach cylinder

  title={The efficiency and the demagnetization field of a general Halbach cylinder},
  author={Rasmus Bj{\o}rk and Aw Smith and Christian R. H. Bahl},
  journal={Journal of Magnetism and Magnetic Materials},
Abstract The maximum magnetic efficiency of a general multipole Halbach cylinder of order p is found as function of p . The efficiency is shown to decrease for increasing absolute value of p . The optimal ratio between the inner and outer radius, i.e. the ratio resulting in the most efficient design, is also found as function of p and is shown to tend towards smaller and smaller magnet sizes. Finally, the demagnetizing field in a general p -Halbach cylinder is calculated, and it is shown that… Expand

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