A method of magnetizing metal, including the steps of: positioning metal to be magnetized in a magnetic field produced by magnetic vector potential; and positioning, in the magnetic field, at least one magnetic-vector-potential inductor which induces the magnetic vector potential, such that the at least one magnetic-vector-potential inductor is located adjacent to the metal for magnetizing the metal, the at least one magnetic-vector-potential inductor having relative permeability whose absolute value is larger than an absolute value of relative permeability of the metal.